T-G3 — Priority job queue

[lightningpixel]

Epic: Epic G — VRAM pre-flight & job queue
Priority: P2

Context

There is currently no job queue: _jobs in workflow_runs.py is an unordered dict with no scheduling or priorities, so nothing prevents concurrent launches from saturating the GPU.

Scope

• Replace the _jobs dict with a real queue (FIFO + priority), to stack generations and heavy ops without a concurrent launch saturating the GPU.

Acceptance criteria

Launching 3 generations in a row runs them serially with a visible "queued" status — no attempt at a simultaneous launch.

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From ROADMAP_0.5.md.