feat(aztec-nr): collect missing-annotation errors instead of halting #[aztec]

[vezenovm]

Fixes F-578

check_each_fn_macroified panicked on the first function missing #[external]/#[internal]/#[test], halting #[aztec] before self/context were injected and cascading "cannot find self" across every other function. It now uses std::meta::error to record the diagnostic and continue, so each unannotated function is reported at its own location and the rest of the pipeline runs. Drops the bob_token compile-failure fixture from 38 to 11 errors.

First of a three-PR F-578 stack; followed by #24110 (flip all validators) and #24111 (emit dummies).