revert(cron): remove per-job profile support (PR #28124) (#43956)

Fully removes the cron per-job 'profile' arg added in #28124: the
cronjob tool schema field, CLI --profile flags on cron create/edit,
job-record storage/validation, the scheduler's _job_profile_context
wrapper, and the script-runner env override. Sequential-partition
logic reverts to workdir-only.

The context-local HERMES_HOME override in hermes_constants and the
subprocess bridging in tools/environments/local.py are kept — they
now have other consumers (dashboard multi-profile, TUI gateway).

hermes_cli/subcommands/cron.py

@@ -70,10 +70,6 @@ def build_cron_parser(subparsers, *, cmd_cron: Callable) -> None:
         "--workdir",
         help="Absolute path for the job to run from. Injects AGENTS.md / CLAUDE.md / .cursorrules from that directory and uses it as the cwd for terminal/file/code_exec tools. Omit to preserve old behaviour (no project context files).",
     )
-    cron_create.add_argument(
-        "--profile",
-        help="Hermes profile name to run the job under. Use 'default' for the root profile. Named profiles must already exist. Omit to preserve the scheduler's existing profile.",
-    )
 
     # cron edit
     cron_edit = cron_subparsers.add_parser(
@@ -138,10 +134,6 @@ def build_cron_parser(subparsers, *, cmd_cron: Callable) -> None:
         "--workdir",
         help="Absolute path for the job to run from (injects AGENTS.md etc. and sets terminal cwd). Pass empty string to clear.",
     )
-    cron_edit.add_argument(
-        "--profile",
-        help="Hermes profile name to run the job under. Use 'default' for the root profile. Pass empty string to clear.",
-    )
 
     # lifecycle actions
     cron_pause = cron_subparsers.add_parser("pause", help="Pause a scheduled job")