feat: add deterministic brand pipeline and core assets #41

Parent

Part of #40.

What to build

Give ffmpegfyMe a maintainable visual identity and reproducible assets. Contributors can regenerate the canonical artwork and verify that committed outputs match their sources and verified project facts.

Acceptance criteria

• Canonical artwork uses tracked SVG sources; handwritten glyphs are vector paths and need no runtime font.
• The primary mark uses one film-strip frame around handwritten ff, followed by MPEGfyMe; frame and MPEG use #cad3f5, and fyMe uses Sky #91d7e3.
• A simplified favicon uses the film frame, ff, superscript fy, and a fallback readable at small sizes.
• README and GitHub social banners have canonical SVG sources. Raster derivatives are generated only when a platform requires them.
• Banner design uses the approved tagline and only verified facts: MP4/MKV outputs, up to three attempts per item, and a 60-second default inactivity timeout.
• Social banner presents the approved implemented feature pillars: authenticated HTTP/HLS, MP4/MKV stream copy, and resumable batches with retries.
• The palette uses Catppuccin Macchiato with Sky #91d7e3 as accent and the approved supporting tokens.
• task brand:generate produces assets deterministically from repository-tracked sources and data.
• task brand:check detects missing or stale generated assets, and CI runs the check.
• New task descriptions and generated assets contain no emoji characters.