feat(session): adapter HTTP OpenAI-compatible pour profils locaux/LAN (#14)

Ajoute un adapter de session HTTP OpenAI-compatible, purement additif,
permettant d'intégrer des modèles locaux/LAN comme profils IdeA canoniques
avec parité tool-calling/MCP.

- domain: extension du profil et des ports pour l'adapter OpenAI-compatible
- infrastructure: adapter openai_compat + routage factory
- app-tauri: mapping des outils OpenAI (openai_tools) + wiring state/lib
- application: catalogue d'agents + tests de use-cases profils

Validé QA (backend GO): round-trip byte-identique Claude/Codex, mapping
erreurs, dégradation tools, conversation_id None, conformance un seul Final,
routage factory. Suites vertes domain 467 / application 530 /
infrastructure 523 / app-tauri 247, 0 échec.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Cargo.toml

@@ -18,6 +18,7 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 thiserror = "2"
 async-trait = "0.1"
+futures-util = "0.3"
 tokio = { version = "1", features = ["rt-multi-thread", "macros", "sync", "fs", "io-util", "time"] }
 # Local git via libgit2. Network features (https/ssh → openssl) are off for L8:
 # only local operations (status/commit/branch/checkout/log) are in scope; remote