chore: apply gapman rebrand to LangChain adapter files (follow-up to #74)

- docs/adapters/langchain.md: gitagent <verb> → gapman <verb> in all CLI
  examples; @shreyaskapale/gitagent → @open-gitagent/gapman package ref
- src/adapters/langchain.ts: 'Generated by gitagent export' →
  'Generated by gapman export' (user-visible string in generated scripts)
- src/runners/langchain.ts: venv path gitagent-env → langchain-venv
  (matches the path documented in the PR and adapter docs)

Prose references to 'gitagent' as the protocol/project name preserved
as per #74 policy.

Author: AJAmit17

docs/adapters/langchain.md

@@ -7,7 +7,7 @@ Complete mapping guide for converting gitagent agents to LangChain Python code.
 LangChain is a popular framework for building applications with large language models. The gitagent LangChain adapter generates standalone Python scripts that use LangChain's agent framework with support for:
 
 - **Multi-provider support**: OpenAI (GPT-4, o1, o3) and Anthropic (Claude)
-- **Tool integration**: Converts gitagent tool definitions to LangChain `@tool` decorators
+- **Tool integration**: Converts gapman tool definitions to LangChain `@tool` decorators
 - **Sub-agent delegation**: Maps gitagent sub-agents to LangChain agent delegates
 - **Memory management**: Automatic memory handling via `create_agent()`
 - **System prompts**: Combines SOUL.md, RULES.md, skills, and knowledge into unified prompt
@@ -25,7 +25,7 @@ The gitagent LangChain adapter enables:
 python --version
 
 # Install gitagent
-npm install -g @shreyaskapale/gitagent
+npm install -g @open-gitagent/gapman
 ```
 
 ### LangChain Dependencies
@@ -86,20 +86,20 @@ The adapter automatically detects the provider based on model name:
 
 ```bash
 # Export to stdout
-gitagent export --format langchain -d ./my-agent
+gapman export --format langchain -d ./my-agent
 
 # Save to file
-gitagent export --format langchain -d ./my-agent -o agent.py
+gapman export --format langchain -d ./my-agent -o agent.py
 
 # Export from git repository
-gitagent export --format langchain --repo https://github.com/user/agent.git -o agent.py
+gapman export --format langchain --repo https://github.com/user/agent.git -o agent.py
 ```
 
 **Output Structure:**
 ```python
 """
 LangChain agent definition for my-agent v1.0.0
-Generated by gitagent export
+Generated by gapman export
 
 Prerequisites:
   pip install langchain langchain-openai
@@ -151,18 +151,18 @@ if __name__ == "__main__":
 
 ```bash
 # Run agent using LangChain adapter
-gitagent run ./my-agent --adapter langchain
+gapman run ./my-agent --adapter langchain
 
 # Run with custom prompt
-gitagent run ./my-agent --adapter langchain -p "Explain quantum computing"
+gapman run ./my-agent --adapter langchain -p "Explain quantum computing"
 
 # Run from git repository
-gitagent run --repo https://github.com/user/agent.git --adapter langchain
+gapman run --repo https://github.com/user/agent.git --adapter langchain
 ```
 
 **What Happens:**
 1. Generates LangChain Python script in temporary file
-2. Creates/reuses Python virtual environment at `~/.gitagent/gitagent-env`
+2. Creates/reuses Python virtual environment at `~/.gitagent/langchain-venv`
 3. Installs required packages (langchain, provider packages)
 4. Executes the script with the agent directory as working directory
 5. Cleans up temporary script file on exit
@@ -186,7 +186,7 @@ python agent.py "What is quantum computing?"
 
 ### Input Schema Conversion
 
-gitagent tool YAML schemas are converted to Python type hints:
+gapman tool YAML schemas are converted to Python type hints:
 
 | JSON Schema Type | Python Type |
 |-----------------|-------------|
@@ -498,7 +498,7 @@ export ANTHROPIC_API_KEY=sk-ant-...
    export ANTHROPIC_API_KEY=your-key
    ```
 
-2. **Use virtual environment** - the runner creates one automatically at `~/.gitagent/gitagent-env`
+2. **Use virtual environment** - the runner creates one automatically at `~/.gitagent/langchain-venv`
 
 3. **Monitor token usage** - LangChain doesn't enforce max_tokens strictly
 
@@ -549,10 +549,10 @@ export ANTHROPIC_API_KEY=sk-ant-your-key-here
 **Solution:**
 ```bash
 # Manually install in the venv
-~/.gitagent/gitagent-env/bin/pip install langchain langchain-openai
+~/.gitagent/langchain-venv/bin/pip install langchain langchain-openai
 
 # Or delete venv and let runner recreate it
-rm -rf ~/.gitagent/gitagent-env
+rm -rf ~/.gitagent/langchain-venv
 ```
 
 ### "Python 3 not found"

src/adapters/langchain.ts

@@ -80,7 +80,7 @@ export function exportToLangChain(dir: string): string {
   // --- Docstring ---
   lines.push('"""');
   lines.push(`LangChain agent definition for ${manifest.name} v${manifest.version}`);
-  lines.push('Generated by gitagent export');
+  lines.push('Generated by gapman export');
   lines.push('');
   lines.push('Prerequisites:');
   lines.push(`  pip install ${pipPackages.join(' ')}`);

src/runners/langchain.ts

@@ -55,8 +55,8 @@ export function runWithLangChain(agentDir: string, _manifest: AgentManifest, opt
     process.exit(1);
   }
 
-  // Persistent venv at ~/.gitagent/gitagent-env — reused across runs
-  const venvDir = join(homedir(), '.gitagent', 'gitagent-env');
+  // Persistent venv at ~/.gitagent/langchain-venv — reused across runs
+  const venvDir = join(homedir(), '.gitagent', 'langchain-venv');
   const packages = ['langchain', 'langchain-core', providerInfo.pipPackage];
 
   // --- Step 1: create venv if it doesn't exist ---