feat: isolate Claude and Codex session sources

Persist platform_source across session creation, transcript ingestion, API query paths, and viewer state so Claude and Codex data can coexist without bleeding into each other.

- add platform-source normalization helpers and persist platform_source in sdk_sessions via migration 24 with backfill and indexing
- thread platformSource through CLI hooks, transcript processing, context generation, pagination, search routes, SSE payloads, and session management
- expose source-aware project catalogs, viewer tabs, context preview selectors, and source badges for observations, prompts, and summaries
- start the transcript watcher from the worker for transcript-based clients and preserve platform source during Codex ingestion
- auto-start the worker from the MCP server for MCP-only clients and tighten stdio-driven cleanup during shutdown
- keep createSDKSession backward compatible with existing custom-title callers while allowing explicit platform source forwarding

src/cli/handlers/context.ts

@@ -12,6 +12,7 @@ import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 import { logger } from '../../utils/logger.js';
 import { SettingsDefaultsManager } from '../../shared/SettingsDefaultsManager.js';
 import { USER_SETTINGS_PATH } from '../../shared/paths.js';
+import { normalizePlatformSource } from '../../shared/platform-source.js';
 
 export const contextHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
@@ -31,6 +32,7 @@ export const contextHandler: EventHandler = {
     const cwd = input.cwd ?? process.cwd();
     const context = getProjectContext(cwd);
     const port = getWorkerPort();
+    const platformSource = normalizePlatformSource(input.platform);
 
     // Check if terminal output should be shown (load settings early)
     const settings = SettingsDefaultsManager.loadFromFile(USER_SETTINGS_PATH);
@@ -38,7 +40,7 @@ export const contextHandler: EventHandler = {
 
     // Pass all projects (parent + worktree if applicable) for unified timeline
     const projectsParam = context.allProjects.join(',');
-    const apiPath = `/api/context/inject?projects=${encodeURIComponent(projectsParam)}`;
+    const apiPath = `/api/context/inject?projects=${encodeURIComponent(projectsParam)}&platformSource=${encodeURIComponent(platformSource)}`;
     const colorApiPath = `${apiPath}&colors=true`;
 
     // Note: Removed AbortSignal.timeout due to Windows Bun cleanup issue (libuv assertion)

src/cli/handlers/file-edit.ts

@@ -9,6 +9,7 @@ import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js'
 import { ensureWorkerRunning, workerHttpRequest } from '../../shared/worker-utils.js';
 import { logger } from '../../utils/logger.js';
 import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
+import { normalizePlatformSource } from '../../shared/platform-source.js';
 
 export const fileEditHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
@@ -20,6 +21,7 @@ export const fileEditHandler: EventHandler = {
     }
 
     const { sessionId, cwd, filePath, edits } = input;
+    const platformSource = normalizePlatformSource(input.platform);
 
     if (!filePath) {
       throw new Error('fileEditHandler requires filePath');
@@ -42,6 +44,7 @@ export const fileEditHandler: EventHandler = {
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({
           contentSessionId: sessionId,
+          platformSource,
           tool_name: 'write_file',
           tool_input: { filePath, edits },
           tool_response: { success: true },

src/cli/handlers/observation.ts

@@ -11,6 +11,7 @@ import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 import { isProjectExcluded } from '../../utils/project-filter.js';
 import { SettingsDefaultsManager } from '../../shared/SettingsDefaultsManager.js';
 import { USER_SETTINGS_PATH } from '../../shared/paths.js';
+import { normalizePlatformSource } from '../../shared/platform-source.js';
 
 export const observationHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
@@ -22,6 +23,7 @@ export const observationHandler: EventHandler = {
     }
 
     const { sessionId, cwd, toolName, toolInput, toolResponse } = input;
+    const platformSource = normalizePlatformSource(input.platform);
 
     if (!toolName) {
       // No tool name provided - skip observation gracefully
@@ -51,6 +53,7 @@ export const observationHandler: EventHandler = {
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({
           contentSessionId: sessionId,
+          platformSource,
           tool_name: toolName,
           tool_input: toolInput,
           tool_response: toolResponse,

src/cli/handlers/session-complete.ts

@@ -12,6 +12,7 @@
 import type { EventHandler, NormalizedHookInput, HookResult } from '../types.js';
 import { ensureWorkerRunning, workerHttpRequest } from '../../shared/worker-utils.js';
 import { logger } from '../../utils/logger.js';
+import { normalizePlatformSource } from '../../shared/platform-source.js';
 
 export const sessionCompleteHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
@@ -23,6 +24,7 @@ export const sessionCompleteHandler: EventHandler = {
     }
 
     const { sessionId } = input;
+    const platformSource = normalizePlatformSource(input.platform);
 
     if (!sessionId) {
       logger.warn('HOOK', 'session-complete: Missing sessionId, skipping');
@@ -39,7 +41,8 @@ export const sessionCompleteHandler: EventHandler = {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({
-          contentSessionId: sessionId
+          contentSessionId: sessionId,
+          platformSource
         })
       });
 

src/cli/handlers/session-init.ts

@@ -12,6 +12,7 @@ import { HOOK_EXIT_CODES } from '../../shared/hook-constants.js';
 import { isProjectExcluded } from '../../utils/project-filter.js';
 import { SettingsDefaultsManager } from '../../shared/SettingsDefaultsManager.js';
 import { USER_SETTINGS_PATH } from '../../shared/paths.js';
+import { normalizePlatformSource } from '../../shared/platform-source.js';
 
 export const sessionInitHandler: EventHandler = {
   async execute(input: NormalizedHookInput): Promise<HookResult> {
@@ -42,6 +43,7 @@ export const sessionInitHandler: EventHandler = {
     const prompt = (!rawPrompt || !rawPrompt.trim()) ? '[media prompt]' : rawPrompt;
 
     const project = getProjectName(cwd);
+    const platformSource = normalizePlatformSource(input.platform);
 
     logger.debug('HOOK', 'session-init: Calling /api/sessions/init', { contentSessionId: sessionId, project });
 
@@ -52,7 +54,8 @@ export const sessionInitHandler: EventHandler = {
       body: JSON.stringify({
         contentSessionId: sessionId,
         project,
-        prompt
+        prompt,
+        platformSource
       })
     });