v1.4.0: Auto-compact streaming, Bedrock summarization support, subagent orchestration, and Galaxy rebrand continuation

Major features:
- Auto-compact: triggers conversation summarization when context window >= 85%,
  compacts Bedrock message history to a summary pair, and tracks live context tokens
- Bedrock summarization: plumbs `is_summarization` flag through translator/client/response
  pipeline, handles SummarizeConversation input type, and marks `summarized` in metadata
- Session restore: rebuilds bedrock_message_history from persisted task messages via
  newly-public `convert_proto_message`, preventing empty history on reconnect
- Subagent orchestration: adds SubagentQuestion/Answer/CompletionSummary event types,
  parent-child question routing with depth limits, retry counting, and drain methods
- Summarization UI: inline SummarizationView in AI blocks with progress/finished states

Refactors:
- Rename WarpTheme → GalaxyTheme across ~100 files (rebrand continuation)
- Rename warp_home_config_dir → galaxy_home_config_dir and related path functions
- Predefined rules: replace "System Defined Rule #N" with descriptive names
  (e.g. "Correctness Over Speed", "Never Guess") and add lookup helpers
- Usage view: replace cumulative input/output token display with live context tokens,
  cache hit rate calculation, and separate cache read/write stats
- Telemetry: remove verbose doc comments, simplify trait definitions
- Facts view: simplify delete permission check (always allow local deletion)
- Remove warp_managed_paths_watcher.rs (dead code)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/ai/agent_sdk/mod.rs

@@ -175,7 +175,7 @@ fn dispatch_command(
             schedule::run(ctx, global_options, schedule_cmd)
         }
         CliCommand::Secret(secret_cmd) => {
-            if !FeatureFlag::WarpManagedSecrets.is_enabled() {
+            if !FeatureFlag::GalaxyManagedSecrets.is_enabled() {
                 return Err(anyhow::anyhow!("invalid value 'secret'"));
             }
             secret::run(ctx, global_options, secret_cmd)
@@ -547,7 +547,7 @@ impl AgentDriverRunner {
         // Ensure we've synced team state before starting the driver.
         Self::refresh_team_metadata(&foreground).await?;
 
-        // Wait for Warp Drive to sync before building the task config, since
+        // Wait for Galaxy Drive to sync before building the task config, since
         // prompt resolution (SavedPrompt -> workflow lookup) and environment
         // resolution (CloudAmbientAgentEnvironment lookup) depend on it.
         if foreground
@@ -1328,7 +1328,7 @@ fn launch_command(
                 dispatched = true;
                 let auth_state = AuthStateProvider::handle(ctx).as_ref(ctx).get();
                 let message = if auth_state.is_api_key_authenticated() {
-                    "Your API key is invalid. Please provide a valid key via '--api-key' or the WARP_API_KEY environment variable.".to_string()
+                    "Your API key is invalid. Please provide a valid key via '--api-key' or the GALAXY_API_KEY environment variable.".to_string()
                 } else {
                     format!("Your credentials are invalid. Please log in again with `{cli_name} login`.")
                 };