feat: make rusty-claude-cli usable end-to-end

Wire the CLI to the Anthropic client, runtime conversation loop, and MVP in-tree tool executor so prompt mode and the default REPL both execute real turns instead of scaffold-only commands.

Constraint: Proxy auth uses ANTHROPIC_AUTH_TOKEN as the primary x-api-key source and may stream extra usage fields
Constraint: Must preserve existing scaffold commands while enabling real prompt and REPL flows
Rejected: Keep prompt mode on the old scaffold path | does not satisfy end-to-end CLI requirement
Rejected: Depend solely on raw SSE message_stop from proxy | proxy/event differences required tolerant parsing plus fallback handling
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Keep prompt mode tool-free unless the one-shot path is explicitly expanded and reverified against the proxy
Tested: cargo test -p api; cargo test -p tools; cargo test -p runtime; cargo test -p rusty-claude-cli; cargo build; cargo run -p rusty-claude-cli -- prompt "say hello"; printf '/quit\n' | cargo run -p rusty-claude-cli --
Not-tested: Full interactive tool_use roundtrip against the proxy in REPL mode

rust/crates/runtime/src/lib.rs

@@ -1,13 +1,16 @@
+mod bash;
 mod bootstrap;
 mod compact;
 mod config;
 mod conversation;
+mod file_ops;
 mod json;
 mod permissions;
 mod prompt;
 mod session;
 mod usage;
 
+pub use bash::{execute_bash, BashCommandInput, BashCommandOutput};
 pub use bootstrap::{BootstrapPhase, BootstrapPlan};
 pub use compact::{
     compact_session, estimate_session_tokens, format_compact_summary,
@@ -21,6 +24,11 @@ pub use conversation::{
     ApiClient, ApiRequest, AssistantEvent, ConversationRuntime, RuntimeError, StaticToolExecutor,
     ToolError, ToolExecutor, TurnSummary,
 };
+pub use file_ops::{
+    edit_file, glob_search, grep_search, read_file, write_file, EditFileOutput, GlobSearchOutput,
+    GrepSearchInput, GrepSearchOutput, ReadFileOutput, StructuredPatchHunk, TextFilePayload,
+    WriteFileOutput,
+};
 pub use permissions::{
     PermissionMode, PermissionOutcome, PermissionPolicy, PermissionPromptDecision,
     PermissionPrompter, PermissionRequest,