feat(KEEP-143): add exec, proto, tpl command aliases

[eskp]

Summary

• Adds exec alias to execute command (alongside existing ex)
• Adds proto alias to protocol command (alongside existing pr)
• Adds tpl alias to template command (alongside existing tp)
• Adds exec alias to workflow run subcommand (alongside existing r)
• Updates TestAllNounAliasesResolve to cover the new top-level aliases

Note: workflow already had wf and workflow list already had ls, so no changes needed there.

Test plan

• go build ./... passes
• go vet ./... passes
• go test ./... -count=1 all tests pass, including updated alias resolution test