Bump version to 0.18.15-beta and update changelog

- Bumped version to 0.18.15-beta in Project.toml
- Added comprehensive changelog entry for 0.18.15-beta covering:
  - Philosophy documentation additions
  - Documentation build improvements
  - Bug fixes (TestRunner auto-discovery, typed exceptions)
  - Code quality improvements (import qualification, cleanup)
- Added non-breaking note to BREAKINGS.md for 0.18.15-beta
- All changes are internal or documentation-only; no breaking changes

Author: ocots

BREAKINGS.md

@@ -2,6 +2,18 @@
 
 This document outlines all breaking changes introduced in CTBase v0.18.0-beta compared to v0.17.4. Use this guide to migrate your code and understand the impact of these changes.
 
+## Non-breaking note (0.18.15-beta)
+
+- **Philosophy documentation**: Added comprehensive code philosophy documentation in `dev/philosophy/` covering modules, types/traits, exceptions, docstrings, testing, and documentation standards. No API changes; purely documentation additions.
+- **Agent guides**: Added `AGENTS.md` and `CLAUDE.md` for agent navigation and project context. No API changes; purely documentation additions.
+- **Documentation build improvements**: Changed `docs/make.jl` build method and fixed cross-references. No API changes; purely documentation improvements.
+- **Typed exceptions**: Replaced untyped `error()` and `ArgumentError` with structured CTBase exceptions in `ext/` files. No API changes; internal error handling improvement.
+- **Import qualification**: Qualified imports in submodules (`using DocStringExtensions` → `import DocStringExtensions: TYPEDEF, TYPEDSIGNATURES`). No API changes; internal code quality improvement.
+- **Code cleanup**: Removed dead ternary branches, fixed byte-indexing, removed circular imports. No API changes; internal code quality improvement.
+- **TestRunner auto-discovery fix**: Fixed non-recursive test discovery in auto-discovery mode. No API changes; bug fix.
+- **Docstring refactoring**: Rewrote ExtensionError and SolverFailure docstrings with `$(TYPEDEF)` and standardized sections. No API changes; documentation improvement.
+- **No migration required**: All changes are internal or documentation-only. No breaking changes.
+
 ## Non-breaking note (0.18.14-beta)
 
 - **TestRunner progress display refactoring**: Renamed `progress` parameter to `show_progress_line` for clarity, and added new `show_progress_bar` parameter for granular control. Users with `progress=false` should change to `show_progress_line=false`. Users with `progress=true` (default) can keep using defaults or set `show_progress_line=true, show_progress_bar=false` for minimal display without the graphical bar. No breaking changes; purely parameter rename with backward-compatible defaults. Migration: replace `progress=` with `show_progress_line=`.

CHANGELOGS.md

@@ -5,6 +5,71 @@ All notable changes to CTBase 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).
 
+## [0.18.15-beta] - 2026-06-06
+
+### 📚 Documentation
+
+#### **Philosophy Documentation**
+
+- **Added philosophy documentation**: Added comprehensive code philosophy documentation in `dev/philosophy/`
+  - `modules.md`: Submodule organization, imports/qualification, DAG, exports
+  - `types-traits-interfaces.md`: Types vs traits, interfaces/contracts, SOLID/DRY/YAGNI, type stability
+  - `exceptions.md`: The 7 exceptions and the choice rule
+  - `docstrings.md`: Docstring templates, cross-references, example safety
+  - `testing.md`: Categories, fakes/stubs, module + callable function template
+  - `documentation.md`: API generation, guides, draft workflow
+- **Added agent guides**: Added `AGENTS.md` (agent navigation guide) and `CLAUDE.md` (Claude project context)
+- **Added planning template**: Added `dev/planning.md` for implementation plans
+- **Added operational rules**: Added `dev/RULES.md` for MCP, doc build, git, and output capture procedures
+
+#### **Documentation Build Improvements**
+
+- **Faster builds**: Changed `docs/make.jl` from `Pkg.activate/instantiate` to `pushfirst!(LOAD_PATH, ...)` for faster builds
+- **Fixed cross-references**: Fixed unresolved `@ref` links for extension tags (AbstractCoveragePostprocessingTag, TestRunnerTag, AbstractTestRunnerTag)
+- **Added examples**: Added example code blocks for extension tags in docstrings
+- **Refactored docstrings**: Rewrote ExtensionError and SolverFailure docstrings with `$(TYPEDEF)`, standardized sections, and cross-references
+
+### 🐛 Bug Fixes
+
+#### **TestRunner Auto-Discovery**
+
+- **Fixed non-recursive discovery**: Fixed test discovery in auto-discovery mode to use `_collect_test_files_recursive` instead of flat `readdir`
+- **Impact**: Tests in subdirectories were silently ignored in auto-discovery mode; now properly collected recursively
+
+#### **Typed Exceptions (Tenet 6)**
+
+- **Replaced untyped errors**: Replaced all `error()` and `ArgumentError` with structured CTBase exceptions across `ext/` files
+  - `ext/TestRunner.jl`: 7 replacements (IncorrectArgument, PreconditionError)
+  - `ext/CoveragePostprocessing.jl`: 4 replacements (PreconditionError)
+  - `ext/DocumenterReference.jl`: 2 replacements (IncorrectArgument)
+- **Fixed invalid Julia syntax**: Fixed 2 occurrences of `catch e::CTBase.Exceptions.CTException` → `catch e` + `e isa ... || rethrow()`
+- **Fixed docstring output**: Corrected incorrect output in `_progress_bar` docstring (width=20 → 10 blocks)
+- **Updated tests**: Updated 7 test files to reflect new exception types
+
+### 🧹 Code Quality
+
+#### **Import Qualification**
+
+- **Qualified imports**: Changed `using DocStringExtensions` to `import DocStringExtensions: TYPEDEF, TYPEDSIGNATURES` in all submodules
+- **Qualified Coverage import**: Changed `using Coverage` to `using Coverage: Coverage` in CoveragePostprocessing
+- **Removed circular import**: Removed `using CTBase` from src/Exceptions/Exceptions.jl
+- **Removed redundant imports**: Removed redundant `using DocStringExtensions` from src/Descriptions/types.jl
+
+#### **Code Cleanup**
+
+- **Removed dead ternary branches**: Simplified `_normalize_selections` and `_builder_to_string` in TestRunner
+- **Fixed byte-indexing**: Changed path slicing from byte-indexing to `relpath()` in CoveragePostprocessing
+- **Fixed collision risk**: Normalized flat names in cov file flattening to prevent collisions
+
+### 🧪 Testing
+
+- **All tests pass**: 1161/1161 tests pass
+- **Documentation builds**: Documentation builds successfully with no extension errors
+
+### 🧹 Maintenance
+
+- **Version bump**: Bumped to 0.18.15-beta for development.
+
 ## [0.18.14-beta] - 2026-05-30
 
 ### ✨ New Features

Project.toml

@@ -1,6 +1,6 @@
 name = "CTBase"
 uuid = "54762871-cc72-4466-b8e8-f6c8b58076cd"
-version = "0.18.14-beta"
+version = "0.18.15-beta"
 authors = ["Olivier Cots <olivier.cots@irit.fr>", "Jean-Baptiste Caillau <caillau@univ-cotedazur.fr>"]
 
 [deps]