Add infrastructure changelog system to task-mcp

Implements session-aware infrastructure change tracking for CF-179.

Changes:
- New changelog.ts with 3 MCP tools:
  - changelog_add: Add infrastructure changes
  - changelog_since_session: Query changes since last session
  - changelog_list: Time-based fallback query
- Integrated with session-start command via MCP
- Database-first architecture (PostgreSQL on infra VM)
- Session-relative queries (not fixed time windows)

Database schema:
- infrastructure_changelog table (6 fields)
- Migrated 5 historical changes
- Indexes on date, session_id, created_at

Task: CF-179

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/index.ts

@@ -26,6 +26,7 @@ import { taskDelegations, taskDelegationQuery } from './tools/delegations.js';
 import { projectLock, projectUnlock, projectLockStatus, projectContext } from './tools/locks.js';
 import { versionAdd, versionList, versionShow, versionUpdate, versionRelease, versionAssignTask } from './tools/versions.js';
 import { taskCommitAdd, taskCommitRemove, taskCommitsList, taskLinkCommits, sessionTasks } from './tools/commits.js';
+import { changelogAdd, changelogSinceSession, changelogList } from './tools/changelog.js';
 import {
   componentRegister,
   componentList,
@@ -287,6 +288,17 @@ server.setRequestHandler(CallToolRequestSchema, async (request) => {
         });
         break;
 
+      // Infrastructure Changelog
+      case 'changelog_add':
+        result = await changelogAdd(a as any);
+        break;
+      case 'changelog_since_session':
+        result = await changelogSinceSession(a as any);
+        break;
+      case 'changelog_list':
+        result = await changelogList(a.days_back, a.limit);
+        break;
+
       // Impact Analysis
       case 'component_register':
         result = JSON.stringify(await componentRegister(a.id, a.name, a.type, {

src/tools/changelog.ts

@@ -0,0 +1,116 @@
+import { query, queryOne } from '../db.js';
+
+interface ChangelogAddArgs {
+  date: string;  // YYYY-MM-DD
+  title: string;
+  change_description: string;
+  impact: string;
+  actions_required?: string;
+  session_id?: string;
+  task_ids?: string[];
+}
+
+interface ChangelogSinceSessionArgs {
+  project: string;  // To find last session for this project
+}
+
+/**
+ * Add infrastructure changelog entry
+ */
+export async function changelogAdd(args: ChangelogAddArgs): Promise<string> {
+  const { date, title, change_description, impact, actions_required, session_id, task_ids } = args;
+
+  await query(
+    `INSERT INTO infrastructure_changelog
+     (date, title, change_description, impact, actions_required, session_id, task_ids)
+     VALUES ($1, $2, $3, $4, $5, $6, $7)
+     ON CONFLICT (date, title) DO NOTHING`,
+    [date, title, change_description, impact, actions_required || null, session_id || null, task_ids || null]
+  );
+
+  return `Changelog entry added: ${date} - ${title}`;
+}
+
+/**
+ * Get infrastructure changes since last session for a project
+ * Returns changes between last session end and now
+ */
+export async function changelogSinceSession(args: ChangelogSinceSessionArgs): Promise<string> {
+  const { project } = args;
+
+  // Find last completed session for this project
+  const lastSession = await queryOne<{ ended_at: string }>(
+    `SELECT ended_at
+     FROM sessions
+     WHERE project = $1 AND status = 'completed' AND ended_at IS NOT NULL
+     ORDER BY ended_at DESC
+     LIMIT 1`,
+    [project]
+  );
+
+  if (!lastSession || !lastSession.ended_at) {
+    // No previous session - show last 7 days as fallback
+    const changes = await query<any>(
+      `SELECT date, title, change_description, impact, actions_required
+       FROM infrastructure_changelog
+       WHERE date >= CURRENT_DATE - INTERVAL '7 days'
+       ORDER BY date DESC`,
+      []
+    );
+
+    if (changes.length === 0) {
+      return '📋 **Infrastructure Changes:** None in last 7 days (no previous session found)';
+    }
+
+    let output = '📋 **Infrastructure Changes (last 7 days, no previous session):**\n';
+    changes.forEach((c: any) => {
+      output += `  • ${c.date}: ${c.title}\n`;
+    });
+    return output;
+  }
+
+  // Query changes since last session ended
+  const changes = await query<any>(
+    `SELECT date, title, change_description, impact, actions_required, task_ids
+     FROM infrastructure_changelog
+     WHERE created_at > $1
+     ORDER BY date DESC`,
+    [lastSession.ended_at]
+  );
+
+  if (changes.length === 0) {
+    const lastDate = new Date(lastSession.ended_at).toISOString().split('T')[0];
+    return `📋 **Infrastructure Changes:** None since last session (${lastDate})`;
+  }
+
+  const lastDate = new Date(lastSession.ended_at).toISOString().split('T')[0];
+  let output = `📋 **Infrastructure Changes (since ${lastDate}):**\n`;
+  changes.forEach((c: any) => {
+    output += `  • ${c.date}: ${c.title}\n`;
+  });
+  return output;
+}
+
+/**
+ * List recent infrastructure changes (fallback, time-based)
+ */
+export async function changelogList(days_back = 7, limit = 20): Promise<string> {
+  const changes = await query<any>(
+    `SELECT date, title, change_description, impact, actions_required, task_ids
+     FROM infrastructure_changelog
+     WHERE date >= CURRENT_DATE - INTERVAL '${days_back} days'
+     ORDER BY date DESC
+     LIMIT $1`,
+    [limit]
+  );
+
+  if (changes.length === 0) {
+    return `📋 **Infrastructure Changes:** None in last ${days_back} days`;
+  }
+
+  let output = `📋 **Infrastructure Changes (last ${days_back} days):**\n`;
+  changes.forEach((c: any) => {
+    output += `  • ${c.date}: ${c.title}\n`;
+  });
+  return output;
+}

src/tools/index.ts

@@ -389,6 +389,47 @@ export const toolDefinitions = [
     },
   },
 
+  // Infrastructure Changelog Tools
+  {
+    name: 'changelog_add',
+    description: 'Add infrastructure change entry for session awareness',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        date: { type: 'string', description: 'Change date (YYYY-MM-DD)' },
+        title: { type: 'string', description: 'Short title (max 100 chars)' },
+        change_description: { type: 'string', description: 'What changed' },
+        impact: { type: 'string', description: 'Effects on existing infrastructure' },
+        actions_required: { type: 'string', description: 'Steps developers need to take (optional)' },
+        session_id: { type: 'string', description: 'Session that implemented change (optional)' },
+        task_ids: { type: 'array', items: { type: 'string' }, description: 'Related task IDs (optional)' },
+      },
+      required: ['date', 'title', 'change_description', 'impact'],
+    },
+  },
+  {
+    name: 'changelog_since_session',
+    description: 'Get infrastructure changes since last session for a project. Use at session start.',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        project: { type: 'string', description: 'Project key (e.g., CF, VPN) to find last session' },
+      },
+      required: ['project'],
+    },
+  },
+  {
+    name: 'changelog_list',
+    description: 'List recent infrastructure changes by time period (fallback)',
+    inputSchema: {
+      type: 'object',
+      properties: {
+        days_back: { type: 'number', description: 'Days to look back (default: 7)' },
+        limit: { type: 'number', description: 'Max results (default: 20)' },
+      },
+    },
+  },
+
   // Project Lock Tools
   {
     name: 'project_lock',