feat(tools): add Google Calendar tools and register Gmail/GCal in daemon

Add calendar.today, calendar.list, calendar.search tools mirroring the
Gmail tool pattern. Includes gcal-auth CLI command, config schema, tool
policy entries (messaging/coding profiles + group:gcal), and 17 tests.
Also wires up gmail and gcal tool registration in the daemon and TUI.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/config/schema.ts

@@ -167,10 +167,18 @@ const heartbeatSchema = z.object({
   disk_threshold_mb: z.number().min(10).default(100),
 }).default({});
 
+const gcalSchema = z.object({
+  enabled: z.boolean().default(false),
+  credentials_file: z.string().optional(),
+  token_file: z.string().default('~/.config/flynn/gcal-token.json'),
+  calendar_ids: z.array(z.string()).default(['primary']),
+}).optional();
+
 const automationSchema = z.object({
   cron: z.array(cronJobSchema).default([]),
   webhooks: z.array(webhookSchema).default([]),
   gmail: gmailSchema,
+  gcal: gcalSchema,
   heartbeat: heartbeatSchema,
 }).default({});
 
@@ -408,5 +416,6 @@ export type HeartbeatConfig = z.infer<typeof heartbeatSchema>;
 export type HeartbeatCheck = z.infer<typeof heartbeatCheckSchema>;
 export type EmbeddingConfig = z.infer<typeof embeddingSchema>;
 export type EmbeddingProvider = z.infer<typeof embeddingProviderSchema>;
+export type GcalConfig = z.infer<typeof gcalSchema>;
 export type PairingCodeConfig = z.infer<typeof pairingSchema>;
 export type LogLevel = z.infer<typeof logLevelSchema>;