feat: v0.7.0 — am run/start --provider/--model : résolution cloud via le registre (base_url + keyring + modèle), fallback cloud quand le modèle local est inconnu, canal model_env/model_arg/env_map, jamais de token en clair (closes #92)

- apply_provider : providers::resolve_for (flag > agent > défaut) + apply_env_map_resolved (api_key = @secret, base_url/model du provider résolu)
- start/run/restart : --provider et --model dans le CLI, le REPL et la complétion ; specs help + man pages
- Tests unitaires : résolution, cascade, canal déclaré, erreur provider inconnu (liste), absence de fuite (env sans valeur sk-), fallback embarqué

src/help.rs

@@ -156,6 +156,18 @@ const START_FLAGS: &[HelpFlag] = &[
         value: "",
         desc: "Run inside the agent's container profile (issue #58)",
     },
+    HelpFlag {
+        short: "",
+        long: "--model",
+        value: "MODEL",
+        desc: "Model to use: local runtime first, then the provider registry (issue #71/#92)",
+    },
+    HelpFlag {
+        short: "",
+        long: "--provider",
+        value: "PROVIDER",
+        desc: "Provider of the registry to use (base_url + keyring token + model) (issue #92)",
+    },
 ];
 
 pub static HELP_SPECS: &[HelpSpec] = &[
@@ -911,7 +923,8 @@ pub static HELP_SPECS: &[HelpSpec] = &[
         about: "Run the agent command directly with the given arguments (no process management).",
         search_terms: &["exec", "pass-through", "container", "docker", "podman"],
         flags: &[
-            HelpFlag { short: "", long: "--model", value: "MODEL", desc: "Local model to use (issue #71)" },
+            HelpFlag { short: "", long: "--model", value: "MODEL", desc: "Model to use: local runtime first, then the provider registry (issue #71/#92)" },
+            HelpFlag { short: "", long: "--provider", value: "PROVIDER", desc: "Provider of the registry to use (base_url + keyring token + model) (issue #92)" },
             HelpFlag { short: "", long: "--container", value: "", desc: "Run inside the agent's container profile (issue #58)" },
         ],
         subcommands: &[],
@@ -922,6 +935,7 @@ pub static HELP_SPECS: &[HelpSpec] = &[
         io: None,
         examples: &[
             HelpExample { desc: "Run an agent command directly.", code: "run claude-code" },
+            HelpExample { desc: "Use a provider of the registry.", code: "run claude-code --provider anthropic --model claude-sonnet-4" },
             HelpExample { desc: "Pass --help through to the agent (after --).", code: "run claude-code -- --help" },
         ],
     },