docs: add wiki pages for all audiences, fix .old.yml leak

9 new wiki pages: getting-started, faq, troubleshooting,
advanced-usage, verification-modes, adding-a-platform,
adding-a-scraper, testing-guide, release-process.

Updated architecture.md with mermaid diagrams, tools.md with
full pipeline and target/exporter sections, profiling.md with
missing fields, index.md with glossary and nav links.

Expanded CONTRIBUTING.md from stub to full contributor guide.

Filter .old.yml from load_emulator_profiles, generate_db alias
collection, and generate_readme counts. Fix BizHawk sha1 mode
in tools.md, fix RetroPie path, fix export_truth.py typos.

mkdocs.yml

@@ -37,7 +37,11 @@ markdown_extensions:
 - toc:
     permalink: true
 - pymdownx.details
-- pymdownx.superfences
+- pymdownx.superfences:
+    custom_fences:
+    - name: mermaid
+      class: mermaid
+      format: !!python/name:pymdownx.superfences.fence_code_format
 - pymdownx.tabbed:
     alternate_style: true
 plugins:
@@ -132,7 +136,7 @@ nav:
   - ZC: systems/zc.md
 - Emulators:
   - Overview: emulators/index.md
-  - Official ports (62):
+  - Official ports (63):
     - amiarcadia: emulators/amiarcadia.md
     - Amiberry: emulators/amiberry.md
     - Ardens: emulators/ardens.md
@@ -180,6 +184,7 @@ nav:
     - PicoDrive: emulators/picodrive.md
     - play: emulators/play.md
     - PPSSPP: emulators/ppsspp.md
+    - RPCS3: emulators/rpcs3.md
     - Rustation: emulators/rustation.md
     - RVVM: emulators/rvvm.md
     - SameBoy: emulators/sameboy.md
@@ -429,7 +434,7 @@ nav:
     - PCSX-ReARMed: emulators/pcsx_rearmed.md
   - Launchers (1):
     - Dolphin Launcher: emulators/dolphin_launcher.md
-  - Other (24):
+  - Other (23):
     - ares: emulators/ares.md
     - Beetle GBA (Mednafen): emulators/beetle_gba.md
     - BigPEmu: emulators/bigpemu.md
@@ -442,7 +447,6 @@ nav:
     - Model 2 Emulator: emulators/model2.md
     - openMSX: emulators/openmsx.md
     - Redream: emulators/redream.md
-    - RPCS3: emulators/rpcs3.md
     - Ryujinx: emulators/ryujinx.md
     - shadps4: emulators/shadps4.md
     - Supermodel: emulators/supermodel.md
@@ -458,8 +462,17 @@ nav:
 - Gap Analysis: gaps.md
 - Wiki:
   - Overview: wiki/index.md
+  - Getting started: wiki/getting-started.md
+  - FAQ: wiki/faq.md
+  - Troubleshooting: wiki/troubleshooting.md
   - Architecture: wiki/architecture.md
   - Tools: wiki/tools.md
-  - Profiling guide: wiki/profiling.md
+  - Advanced usage: wiki/advanced-usage.md
+  - Verification modes: wiki/verification-modes.md
   - Data model: wiki/data-model.md
+  - Profiling guide: wiki/profiling.md
+  - Adding a platform: wiki/adding-a-platform.md
+  - Adding a scraper: wiki/adding-a-scraper.md
+  - Testing guide: wiki/testing-guide.md
+  - Release process: wiki/release-process.md
 - Contributing: contributing.md