Phase 0: scaffold tree + manifest

- README, .gitignore, CLAUDE.md (project conventions)
- docs/PHASE0.md — full Phase 0 manifest (locked substrate)
- 10 root .lua modules + 4 ffi/ bindings, all stubs raising NotImplemented
  with module-scoped responsibilities matching the manifest
- config.lua wired to current dirac/hossenfelder endpoints (qwen-coder-7b
  snappy/32k + cloud via OpenRouter through hossenfelder)

File names match docs/PHASE0.md §4 exactly. Module bodies fill in across
later phases; the tree shape is locked.

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

renderer.lua

@@ -0,0 +1,19 @@
+-- renderer.lua — output formatting and ANSI sequences.
+-- Phase 0: minimal — assistant text plain-printed; CMD: lines highlighted;
+-- exec output framed. Syntax highlighting hooks land in Phase 5.
+
+local M = {}
+
+function M.assistant(text)
+    error("renderer.assistant: not implemented (Phase 0 pending)")
+end
+
+function M.exec_output(output, exit_code)
+    error("renderer.exec_output: not implemented (Phase 0 pending)")
+end
+
+function M.status(line)
+    error("renderer.status: not implemented (Phase 0 pending)")
+end
+
+return M