feat: add temporal options command and declutter help output

[chaptersix]

Summary

• Adds temporal options command (kubectl-style) that displays global and connection flags in a table with env var and config key columns
• Hides global flags from root --help and connection flags from subcommand --help, replacing them with a hint to temporal options
• Adds hide-from-help, config-key, and Description() support to the option set YAML spec and code generator
• Shortens flag descriptions to remove info now shown in dedicated table columns

Before

$ temporal --help
...
Flags:
      --client-connect-timeout duration   ...
      --color string                      ...
      --command-timeout duration          ...
      ... (15 more global flags)

After

$ temporal --help
...
Use "temporal options" for global and connection options.

$ temporal options
Global options
...
  FLAG                                ENV                    DESCRIPTION
  --env string                        TEMPORAL_ENV           Active environment name ...
  ...

Connection options
...
  FLAG                              ENV                       CONFIG KEY        DESCRIPTION
  --address string                  TEMPORAL_ADDRESS          address           Temporal Service gRPC endpoint ...
  --api-key string                  TEMPORAL_API_KEY          api_key           API key for request
  ...

Test plan

• go build ./cmd/temporal
• go test ./internal/temporalcli/ -run TestHelp
• Verify temporal --help no longer shows global flags
• Verify temporal workflow --help no longer shows connection flags
• Verify temporal workflow list --help shows only command-specific flags
• Verify temporal options displays both tables with correct env/config columns
• Verify all flags still work when passed on the command line