Initial commit: AirCoding V1.0.0 Alpha architecture baseline

Complete architecture document set with multi-model review remediation:
- Frozen interface contracts, runtime semantics, DB schemas
- Event/tool/error/provider registries
- Scheduler and main agent state machines
- C4 module/code views, solution architecture, baseline V1
- Multi-model review reports and joint assessment
- Phase-gate remediation complete (P0/P1/P2/UX resolved)
- Implementation plan with T-000A through T-045
- Reference folders kept as placeholders only

reference/atuin-18.16.1/.codespellrc

@@ -0,0 +1,7 @@
+[codespell]
+# Ref: https://github.com/codespell-project/codespell#using-a-config-file
+skip = .git*,*.lock,.codespellrc,CODE_OF_CONDUCT.md,CONTRIBUTORS
+check-hidden = true
+# ignore-regex = 
+ignore-words-list = crate,ratatui,inbetween,iterm,fo,brunch
+