refactor(main): extract execute/secrets/graph dispatch from main()

[github-actions]

What was complex

main() in src/main.rs was flagged by Clippy's too_many_lines lint at 496/100 lines. The bulk of this was three large match arms handling Commands::Execute, Commands::Secrets, and Commands::Graph, each containing substantial inline logic (including a nested match for Commands::Secrets's SecretsCmd and Commands::Graph's GraphCmd).

What changed

Extracted the logic for these three arms into standalone async helper functions, placed just above main():

• dispatch_execute_command(ExecuteCommandArgs) -> Result<()> — handles the --prepare-custom-agent-output branch and the normal run_execute path. New ExecuteCommandArgs struct groups the CLI-parsed fields.
• dispatch_secrets_command(SecretsCmd) -> Result<()> — handles SecretsCmd::Set / List / Delete.
• dispatch_graph_command(GraphCmd) -> Result<()> — handles GraphCmd::Dump / Deps / Outputs.

main()'s top-level match now has a single, flat call per arm for these commands, matching the pattern already used elsewhere in the file (e.g. run_execute, run_compile).

Result

• main() cognitive/line complexity: 496/100 → 355/100 (still above the artificially low 100-line Clippy threshold used to surface candidates, but a meaningful reduction; a further pass could extract more arms).
• No public API or CLI behavior changes.
• cargo build, cargo test (full suite), and cargo clippy --all-targets --all-features all pass clean (one pre-existing, unrelated field_reassign_with_default warning in create_work_item.rs remains untouched).

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Generated by Cyclomatic Complexity Reducer · auto · 120.6 AIC · ⌖ 5.62 AIC · ⊞ 11.4K · ◷

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