Add optional episode titles to queued and live broadcasts

Store an episode_title on each broadcast, settable from the dashboard
or with set_show.php --title=, and show it under the show name on
index.php and under the heading on live.php.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CLAUDE.md

@@ -27,7 +27,7 @@ Public pages:
 
 Admin backend ([admin/](admin/)):
 - [admin/login.php](admin/login.php), [admin/logout.php](admin/logout.php) — Username/password login.
-- [admin/index.php](admin/index.php) — Dashboard: broadcast status, queue the next show (with an optional date and Eastern start time), switch the live show, clear the queue.
+- [admin/index.php](admin/index.php) — Dashboard: broadcast status, queue the next show (with an optional episode title, date and Eastern start time), switch the live show or its episode title, clear the queue.
 - [admin/shows.php](admin/shows.php), [admin/show_edit.php](admin/show_edit.php) — List, add, edit and delete shows, including the description and icon and background image uploads.
 
 Shared includes:
@@ -39,7 +39,7 @@ Shared includes:
 
 Command-line tools (run over SSH from the site root):
 - [cli/poll_icecast.php](cli/poll_icecast.php) — Cron-run poller that records broadcasts and tracks.
-- [cli/set_show.php](cli/set_show.php) — Lists shows, or queues/sets the show by slug, optionally with a start time (`php cli/set_show.php <slug> 2026-10-30 19:30`). Same behaviour as the dashboard control.
+- [cli/set_show.php](cli/set_show.php) — Lists shows, or queues/sets the show by slug, optionally with a start time and episode title (`php cli/set_show.php <slug> 2026-10-30 19:30 --title="Ethereal and Enya"`). Same behaviour as the dashboard control.
 - [cli/create_admin.php](cli/create_admin.php) — Creates an admin account or resets its password.
 
 Other:
@@ -60,7 +60,7 @@ Other:
 MariaDB on localhost. Credentials live in `config/db_credentials.php`, which is gitignored and uploaded to the server separately. Tables (see [sql/schema.sql](sql/schema.sql)):
 
 - `shows` — the shows, with a unique `slug`, a plain-text `description` (blank lines separate paragraphs) and optional `icon_image` and `background_image` (filenames in `images/backgrounds/`).
-- `broadcasts` — one row per streaming session: pending (`started_at` NULL, queued from the dashboard or `cli/set_show.php`), live (`ended_at` NULL), or ended. `scheduled_at` is the advertised start time shown on `index.php`; the broadcast still starts whenever the stream comes online.
+- `broadcasts` — one row per streaming session: pending (`started_at` NULL, queued from the dashboard or `cli/set_show.php`), live (`ended_at` NULL), or ended. `scheduled_at` is the advertised start time shown on `index.php`; the broadcast still starts whenever the stream comes online. `episode_title` is an optional per-episode title (e.g. "Ethereal and Enya") shown under the show name on `index.php` and under the heading on `live.php`.
 - `played_tracks` — tracks per broadcast. Cleared ten minutes after the broadcast ends; no long-term history is kept.
 - `admins` — admin accounts (username + password hash).
 - `login_attempts` — failed logins by IP, used for throttling.
@@ -128,7 +128,7 @@ Server-only setup (one-time, or when the schema changes):
 
 ## Updating Show Information
 
-The `index.php` sidebar is driven by the database. Before a show, queue it on the admin dashboard (or `php cli/set_show.php <slug> <date> <time>`) with its date and Eastern start time; the sidebar then shows its icon, name, start time (with the UTC conversion) and description, switches to "On the Air Now" while live (with the icon and a "Broadcasting Live" link pointing to `live.php`), and falls back to a short "nothing scheduled" note once nothing is queued. Edit descriptions and icons on the show's admin page.
+The `index.php` sidebar is driven by the database. Before a show, queue it on the admin dashboard (or `php cli/set_show.php <slug> <date> <time>`) with its date, Eastern start time and optional episode title; the sidebar then shows its icon, name, episode title, start time (with the UTC conversion) and description, switches to "On the Air Now" while live (with the icon and a "Broadcasting Live" link pointing to `live.php`), and falls back to a short "nothing scheduled" note once nothing is queued. Edit descriptions and icons on the show's admin page.
 
 The commented-out show blocks in the `#one` section of `index.php` are the hand-written history from before this; leave them as they are.