feat(ai): render Markdown + feed game/Proton/Steam logs to the AI — 0.28.0

1) The explanation popup rendered raw Markdown (### / **). Switched to
   QTextEdit.setMarkdown and told the model to answer in Markdown.
2) On "Explain with AI", also collect recent Proton (~/steam-*.log) and Steam
   console logs (core/gamelogs.py — tail-read, size-bounded) and include them in
   the prompt so the model can correlate log errors with findings and pinpoint
   when things went wrong. Reference-fact matching runs over the logs too.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,16 @@ All notable changes to RigDoctor are recorded here. Format follows
 (`MAJOR.MINOR.PATCH`, pre-1.0). `__version__` and `pyproject.toml` must match the git
 release tag (so the auto-updater, D18, can compare versions).
 
+## [0.28.0] - 2026-05-22
+### Added
+- **AI explanations now include recent game logs.** When you press "Explain with AI" on a
+  diagnostic, RigDoctor also gathers recent **Proton** (`~/steam-<appid>.log`) and **Steam**
+  console logs (`core/gamelogs.py`, tail-read + size-bounded) and passes them to the model, so
+  it can correlate log errors with the sensor findings and pinpoint *when* something went wrong.
+### Fixed
+- The AI explanation popup now **renders Markdown** (headings, bold, lists) instead of showing
+  raw `###`/`**` — `QTextEdit.setMarkdown`, and the model is told to answer in Markdown.
+
 ## [0.27.1] - 2026-05-22
 ### Changed
 - AI assistant: selecting **Ollama** now pre-fills the model field with **`qwen2.5:7b`** (a