feat: #3624658 Take the podcast content model from Varbase Podcasts Base instead of duplicating it

Issue: https://www.drupal.org/project/rightup/issues/3624658

RightUp carried its own copy of the podcast content model — the content type, its eight fields, the form display, the card, full and text_card_medium displays, pathauto — byte-identical to what varbase_podcasts_base ships. Two recipes owned one content type.

This removes those 13 files, applies and requires the base (~1.0.0), and keeps only what belongs to the site template: the podcast-card component, the Canvas templates bound to this theme, the live_feed / search_index / search_result displays, the Podcasts and Last Call pages, and the demo episodes.

One thing is worth knowing: the base does not exclude podcasts from the search index and this template does, so that setting is re-applied as a config action. A duplicate node.type.podcast.yml could not carry it, because the base creates the type first and a recipe leaves existing config alone.

Verified on a fresh Drupal CMS build and install: the podcast type arrives from the base with the search exclusion set, all six view displays present, seven demo episodes imported, and /, /podcasts, /podcasts/last-call and /search?keywords=the all answer 200.

AI-Generated: Yes

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