Harden task claims on job spec pointers

[signerless]

Summary

Adds the on-chain claim_task_with_job_spec path so marketplace task claims can require a matching task_job_spec PDA before work is claimed. This also syncs the Anchor/package generated artifacts and boxes several large account contexts to keep the SBF build clear of stack-offset warnings.

The dependency audit finding from local setup is fixed by moving transitive picomatch from 4.0.3 to 4.0.4 in the lockfile.

Validation

• cargo fmt --manifest-path programs/agenc-coordination/Cargo.toml
• cargo test --manifest-path programs/agenc-coordination/Cargo.toml --lib
• cargo build-sbf --manifest-path programs/agenc-coordination/Cargo.toml (passes; only existing crate-type/LTO warning)
• npm audit --audit-level=high
• npm run artifacts:check
• npm run typecheck
• npm run build
• git diff --check

[signerless]

Cross-repo follow-ups:

• SDK: Expose task job spec claim helpers agenc-sdk#32
• Core/runtime: Harden marketplace task creation agenc-core#351