fix: resolve AHP Transport type mismatch between core and SDKs

- Import AhpTransport and AuthConfig from a3s_code_core::ahp instead of a3s_ahp directly
- This avoids having two different versions of a3s_ahp in the dependency graph
- Enable http, websocket, unix-socket features in core's a3s-ahp dependency
  so all Transport variants are available when re-exported

Author: RoyLin

CHANGELOG.md

@@ -0,0 +1,138 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased] - 2026-04-02
+
+---
+
+## [v1.6.0] - 2026-04-02
+
+### Added
+
+#### Document Parsing
+
+- **XLSB (Excel Binary) Support**: Added calamine-based BIFF12 parsing for XLSB files with proper cell value extraction, supporting Float, Int, Bool, DateTime, DateTimeIso, and DurationIso types. Significantly improves table fidelity for .xlsb files.
+
+- **HWPX Table Extraction**: Added structured table extraction from Korean HWPX documents. Parses `tbl/tr/tc` XML hierarchy and includes `structured_payload` for `tables[]` output.
+
+- **Vision OCR Provider**: New OCR backend supporting OpenAI-compatible vision APIs for document OCR fallback.
+
+  ```hcl
+  document_parser {
+    ocr {
+      enabled  = true
+      model    = "openai/gpt-4.1-mini"
+      api_key  = "sk-..."
+      base_url = "https://api.openai.com/v1"  # optional
+      prompt   = "Extract all text from this document..."
+      max_images = 8
+      dpi     = 144
+    }
+  }
+  ```
+
+  Provider priority: External provider > Vision API (if model+api_key configured) > Builtin tesseract
+
+#### Search Ranking
+
+- **Tabular Query Intent Detection**: Automatically detects when queries relate to tables (keywords: table, column, row, spreadsheet, excel, csv, cell, data, record, etc.) and boosts table line matches by +10 keyword hits plus 1.3x relevance multiplier.
+
+- **Heading Inheritance Boost**: When search matches appear under headings that also match the query, those matches receive a relevance boost (up to 1.3x). Looks backwards to find the closest preceding heading.
+
+### Changed
+
+#### Configuration
+
+- `DocumentOcrConfig` extended with new fields:
+  - `provider: Option<String>` - Backend selection ("vision" or "builtin")
+  - `base_url: Option<String>` - Custom API endpoint
+  - `api_key: Option<String>` - API authentication
+
+#### Dependencies
+
+- Added `calamine = "0.26"` for XLSB parsing
+- Added `reqwest/blocking` feature for Vision API HTTP calls
+
+### Fixed
+
+- Test assertion: `paged_text_blocks_reflow_two_column_preserves_paragraph_breaks` - Corrected expected string "Parser metadata now tracks OCR" vs "Parser metadata now tracks OCR backend"
+
+---
+
+## [v1.5.8] - 2026-03-07
+
+### Added
+
+- Phase 1 structured result surfaces:
+  - `structured_payload` exposed in `agentic_parse` output and metadata
+  - Table payloads in stable machine-readable form
+  - Page-level data in `agentic_parse` output and metadata
+  - Stable `tables[]`, `pages[]`, `elements[]` outputs
+
+- Phase 2 PDF extraction improvements:
+  - lopdf position-aware text extraction
+  - Reduced dependence on weak text fallbacks
+  - Position-aware table detection
+
+- `agentic_search` enhancements:
+  - Chunk context consumption
+  - Tabular content consumption
+  - Page numbers and locators support
+
+### Changed
+
+- `ParsedDocument` extended with `tables: Vec<StructuredTable>` and `pages: Vec<PageInfo>`
+
+### Fixed
+
+- Windows shell compatibility improvements
+
+---
+
+## [v1.5.7] - 2026-02-28
+
+### Added
+
+- Runtime session header support for OpenAI configs
+- Cross-platform environment variable expansion in tests
+
+---
+
+## [v1.5.6] - 2026-02-20
+
+### Added
+
+- Enhanced agent config, document parser, LLM, tools, and SDKs
+- Host shell environment propagation to tool commands
+
+---
+
+## [v1.5.5] - 2026-02-10
+
+### Added
+
+- Zhipu AI client (`ZhipuClient` formerly `GlmClient`)
+- Duplicate tool call circuit breaker
+- Streaming fallback support
+- `agentic_parse` skill
+
+---
+
+## [v1.5.4] - 2026-01-28
+
+### Added
+
+- Session-local skill registries
+
+---
+
+## [v1.5.3] - 2026-01-15
+
+### Added
+
+- Tool schema hardening
+- Slash command output restoration