docs: implement persona-based documentation paths

Implements issue #250 by creating user-centric documentation paths
organized around user goals rather than tools.

Changes:
- Add three persona landing pages:
  * Legal/Compliance professionals
  * Security/SCA professionals
  * Developers/Integrators
- Update homepage with 'Choose Your Path' section
- Fix purldb-project label reference

Each persona page uses appropriate language and workflows for its
target audience, with cross-links between personas where relevant.

All existing documentation remains unchanged - this is an additive
refactor creating new entry points.

Verification:
- Documentation builds with zero warnings
- All link checks pass
- All style checks pass

Closes #250

Author: Gyan Ranjan Panda

docs/source/aboutcode-projects/purldb-project.rst

@@ -1,4 +1,4 @@
-.. purldb-project:
+.. _purldb-project:
 
 PurlDB
 ======

docs/source/index.rst

@@ -16,6 +16,41 @@ AboutCode documentation.
 All community contributions are welcome.
 
 
+----
+
+******************
+Choose Your Path
+******************
+
+AboutCode serves different users with different goals. Choose the path that best
+describes you to find the documentation most relevant to your needs:
+
+**Legal & Compliance Professionals**
+    You're responsible for ensuring license compliance, managing open source policies,
+    or generating attribution documentation. You need high-level summaries and
+    compliance workflows.
+
+    → :ref:`persona-legal-compliance`
+
+**Security & SCA Professionals**
+    You're focused on identifying vulnerabilities, managing security risks, or
+    performing software composition analysis. You need vulnerability scanning and
+    security analysis workflows.
+
+    → :ref:`persona-security-researcher`
+
+**Developers & Integrators**
+    You're integrating AboutCode into your development workflow, CI/CD pipeline, or
+    building applications that consume AboutCode data. You need APIs, CLIs, and
+    automation guides.
+
+    → :ref:`persona-developer-integrator`
+
+.. note::
+    Not sure which path fits you? That's okay! You can explore all paths, and each
+    one includes links to the others where relevant.
+
+
 ----
 
 ********
@@ -27,6 +62,17 @@ Overview
 
    aboutcode-project-overview
 
+**************
+Persona Paths
+**************
+
+.. toctree::
+   :maxdepth: 2
+
+   personas/legal-compliance
+   personas/security-researcher
+   personas/developer-integrator
+
 ************
 Contributing
 ************

docs/source/personas/developer-integrator.rst

@@ -0,0 +1,224 @@
+.. _persona-developer-integrator:
+
+====================================
+For Developers & Integrators
+====================================
+
+Welcome! If you're integrating AboutCode tools into your development workflow, CI/CD
+pipeline, or building applications that consume AboutCode data, you're in the right place.
+
+AboutCode provides powerful APIs, command-line tools, and libraries that you can use to
+automate scanning, generate SBOMs, and integrate license and vulnerability analysis into
+your systems.
+
+What You Can Accomplish
+=======================
+
+With AboutCode, you can:
+
+- **Automate Code Scanning**: Run license and vulnerability scans from the command line or CI/CD
+- **Generate SBOMs Programmatically**: Create CycloneDX and SPDX SBOMs via API or CLI
+- **Integrate with Your Tools**: Use REST APIs to query vulnerability data and package metadata
+- **Build Custom Workflows**: Create pipelines that combine scanning, analysis, and reporting
+- **Parse and Process Results**: Work with structured JSON/YAML output for downstream processing
+
+Key Workflows
+=============
+
+1. Command-Line Scanning
+------------------------
+
+Use ScanCode Toolkit from the command line to scan code, detect licenses, extract
+copyrights, and identify packages.
+
+The CLI provides extensive options for customizing scans, filtering results, and
+generating output in various formats (JSON, YAML, SPDX, CycloneDX).
+
+**Example:**
+
+.. code-block:: bash
+
+    # Basic scan
+    scancode -clpieu --json-pp output.json /path/to/code
+
+    # Scan with license policies
+    scancode --license-policy policies.yml --json output.json /path/to/code
+
+    # Generate SPDX SBOM
+    scancode --spdx output.spdx /path/to/code
+
+**Learn more:** :ref:`scancode-toolkit-project`
+
+**Tools you'll use:** ScanCode Toolkit
+
+2. API Integration
+------------------
+
+ScanCode.io provides a REST API for triggering scans, retrieving results, and managing
+projects programmatically.
+
+You can integrate scanning into your CI/CD pipeline, automate SBOM generation, or build
+custom applications that consume scan data.
+
+**Example:**
+
+.. code-block:: python
+
+    import requests
+
+    # Create a project
+    response = requests.post(
+        'https://your-scancodeio.com/api/projects/',
+        json={'name': 'my-project'},
+        headers={'Authorization': 'Token your-api-token'}
+    )
+
+    # Upload code and run pipeline
+    project_url = response.json()['url']
+    # ... upload files and trigger pipeline
+
+**Learn more:** :ref:`scancodeio-project`
+
+**Tools you'll use:** ScanCode.io API, VulnerableCode API, PurlDB API
+
+3. CI/CD Pipeline Integration
+-----------------------------
+
+Integrate AboutCode scanning into your continuous integration pipeline to catch license
+and security issues early in the development process.
+
+You can use GitHub Actions, GitLab CI, Jenkins, or any CI system that supports running
+command-line tools or making API calls.
+
+**Example (GitHub Actions):**
+
+.. code-block:: yaml
+
+    - name: Scan with ScanCode
+      uses: aboutcode-org/scancode-action@v1
+      with:
+        path: .
+        output: scancode-results.json
+
+**Learn more:** :ref:`scancode-action-project`
+
+**Tools you'll use:** ScanCode Action, ScanCode Toolkit, ScanCode.io
+
+4. Creating and Consuming SBOMs
+-------------------------------
+
+Generate software bills of materials (SBOMs) in industry-standard formats like SPDX
+and CycloneDX.
+
+You can create SBOMs from scan results, import SBOMs from other tools, enrich them with
+additional data, and export them for sharing with customers or partners.
+
+**Learn more:** :ref:`create-sboms` and :ref:`consume-sboms`
+
+**Tools you'll use:** ScanCode Toolkit, ScanCode.io, DejaCode
+
+Recommended Tools & Libraries
+==============================
+
+**ScanCode Toolkit**
+    Command-line scanner with extensive options and multiple output formats. The
+    foundation for all AboutCode scanning.
+
+    :ref:`scancode-toolkit-project`
+
+    GitHub: https://github.com/aboutcode-org/scancode-toolkit
+
+**ScanCode.io**
+    Web application with REST API for running complex scanning pipelines. Supports
+    Docker images, packages, and codebases.
+
+    :ref:`scancodeio-project`
+
+    GitHub: https://github.com/aboutcode-org/scancode.io
+
+**VulnerableCode API**
+    REST API for querying vulnerability data by package, CVE, or PURL.
+
+    :ref:`vulnerablecode-project`
+
+    Public API: https://public.vulnerablecode.io/api/
+
+**PurlDB API**
+    REST API for querying package metadata by PURL.
+
+    https://purldb.readthedocs.io
+
+    Public API: https://public.purldb.io/api/
+
+**Python Libraries**
+    - **license-expression**: Parse and normalize SPDX license expressions
+    - **packageurl-python**: Work with Package URLs (PURLs)
+    - **commoncode**: Common utilities for file handling, hashing, and dates
+    - **extractcode**: Universal archive extraction
+
+    :ref:`license-expression-project`
+
+Working with Package URLs (PURLs)
+==================================
+
+Package URLs (PURLs) are a universal way to identify software packages across all
+ecosystems. AboutCode tools use PURLs extensively.
+
+**Format:**
+
+.. code-block:: text
+
+    pkg:type/namespace/name@version?qualifiers#subpath
+
+**Examples:**
+
+.. code-block:: text
+
+    pkg:npm/express@4.18.2
+    pkg:pypi/django@4.2.0
+    pkg:maven/org.apache.commons/commons-lang3@3.12.0
+    pkg:docker/library/nginx@1.25.0
+
+**Python usage:**
+
+.. code-block:: python
+
+    from packageurl import PackageURL
+
+    purl = PackageURL.from_string('pkg:npm/express@4.18.2')
+    print(purl.type)      # 'npm'
+    print(purl.name)      # 'express'
+    print(purl.version)   # '4.18.2'
+
+Output Formats
+==============
+
+AboutCode tools support multiple output formats:
+
+- **JSON**: Structured data for programmatic processing
+- **YAML**: Human-readable structured data
+- **SPDX**: Industry-standard SBOM format (JSON, YAML, RDF, tag-value)
+- **CycloneDX**: OWASP SBOM standard (JSON, XML)
+- **CSV**: Tabular data for spreadsheet analysis
+- **HTML**: Human-readable reports
+
+Next Steps
+==========
+
+**New to AboutCode?**
+    Start with :ref:`start-scanning-code` to understand the basics.
+
+**Ready to automate?**
+    Check out the ScanCode Toolkit CLI documentation for command-line options.
+
+**Building an integration?**
+    Review the ScanCode.io API documentation for REST endpoints.
+
+**Need to understand the data model?**
+    See :ref:`aboutcode_data` for AboutCode data structures.
+
+**Also need compliance workflows?**
+    Visit :ref:`persona-legal-compliance` for policy management and reporting.
+
+**Interested in security analysis?**
+    Check out :ref:`persona-security-researcher` for vulnerability scanning.