docs: convert all architecture .adoc sections to markdown, prettier-format all .md

- Converted 13 individual .adoc section files to .md via
  asciidoctor→docbook5→pandoc(gfm) + post-processing, placed alongside
  the .adoc sources in Docs/Architecture/
- Rebuilt architecture.md from the individual section .md files
- Ran prettier --write on all .md in the repo (23 files changed):
  normalised table column alignment, trailing whitespace, line breaks
- Added .agents/ to .prettierignore (vendored third-party content)
- All .md now passes prettier --check

Docs/Architecture/10_quality_requirements.md

@@ -0,0 +1,26 @@
+# Quality Requirements
+
+## Quality Requirements Overview
+
+| Category | Requirement | Priority |
+| --- | --- | --- |
+| Performance efficiency | 60 FPS at 2560×1440, documented preset, no frame generation | 1 |
+| Reliability / Terrain | Zero raycast holes across sidewalks and carriageway (84-sample transect) | 1 |
+| Accuracy / Fidelity | Building placement matches reference photography within ~1 m | 2 |
+| Accuracy / Fidelity | Street scale (lane width, sidewalk width) within ~10 cm of measured profile | 2 |
+| Usability | WASD + mouse look, jump, reset (R), pause (Escape) — no tutorial needed | 2 |
+| Compliance | ODbL attribution visible at runtime | 2 |
+| Maintainability | Fresh checkout builds with documented engine installation | 2 |
+| Portability | Linux build packages and runs; Windows build ships | 3 |
+
+## Quality Scenarios
+
+| ID | Source/Stimulus | Response | Metric |
+| --- | --- | --- | --- |
+| QS-1 | Player walks both sides of the demo | No fall-through, character stays at ground Z | 0 raycast holes in 84-sample transect |
+| QS-2 | Player holds W for 2 s on flat road | Character moves forward | ≥ 200 cm displacement, Z constant within ±5 cm |
+| QS-3 | Player presses R | Character teleports to spawn | < 100 cm from `StartLocation` |
+| QS-4 | Player presses Escape | Game pauses, cursor appears | `IsGamePaused()` = true |
+| QS-5 | Player presses Escape while paused | Game unpauses, cursor hides | `IsGamePaused()` = false |
+| QS-6 | Game runs on dev workstation at 1440p | Frame rate stable | ≥ 60 FPS, 99th percentile ≥ 55 FPS |
+| QS-7 | Fresh checkout + engine install | Build succeeds | Exit code 0, runnable binary produced |