refactor: Cross-platform build scripts and session format cleanup

- Add scripts/set-version.mjs for cross-platform VITE_APP_VERSION setting
  (replaces bash-specific env var syntax that failed on Windows)
- Extract magic numbers into CLAUDE_SESSION_PARSE_LIMITS and CLAUDE_PRICING
  constants for better maintainability
- Remove legacy session format migration code - sessions now require aiTabs
- Fix session ID regex patterns to properly parse -ai-{tabId} format
- Remove deprecated aiLogs fallbacks - logs are exclusively in aiTabs now

Claude ID: bfd92ffb-a375-47be-94c5-fe4186325092
Maestro ID: b9bc0d08-5be2-4fdf-93cd-5618a8d53b35

scripts/set-version.mjs

@@ -0,0 +1,56 @@
+#!/usr/bin/env node
+/**
+ * Cross-platform script to set VITE_APP_VERSION environment variable
+ * with the local git hash. Works on Windows, macOS, and Linux.
+ *
+ * Usage: node scripts/set-version.mjs <command> [args...]
+ * Example: node scripts/set-version.mjs npm run build
+ */
+
+import { execFileSync, spawn } from 'child_process';
+import process from 'process';
+
+function getGitHash() {
+  try {
+    const hash = execFileSync('git', ['rev-parse', '--short=8', 'HEAD'], {
+      encoding: 'utf8',
+      stdio: ['pipe', 'pipe', 'pipe']
+    }).trim();
+    return hash;
+  } catch {
+    return 'unknown';
+  }
+}
+
+const gitHash = getGitHash();
+const version = `LOCAL ${gitHash}`;
+
+// Set environment variable
+process.env.VITE_APP_VERSION = version;
+
+// Get the command and args to run
+const [,, ...args] = process.argv;
+
+if (args.length === 0) {
+  console.log(`VITE_APP_VERSION=${version}`);
+  process.exit(0);
+}
+
+// Run the command with the environment variable set
+const command = args[0];
+const commandArgs = args.slice(1);
+
+const child = spawn(command, commandArgs, {
+  stdio: 'inherit',
+  shell: true,
+  env: { ...process.env, VITE_APP_VERSION: version }
+});
+
+child.on('close', (code) => {
+  process.exit(code ?? 0);
+});
+
+child.on('error', (err) => {
+  console.error(`Failed to run command: ${err.message}`);
+  process.exit(1);
+});