fix(cli): mem0 init --agent now triggers bootstrap (Node) + created_via parity

External sandbox audit (Sandbox E2E Test Report 2026-05-13) surfaced
two CLI issues.

1. Node — `mem0 init --agent` silently falls through to the non-TTY
   error when no agent env var is set. Commander resolves the
   program-level `--agent` alias (for --json) before init's own
   `--agent`; init's opts.agent stays false. Fix: enable Commander's
   positional options so flags AFTER a subcommand belong to that
   subcommand. Now `mem0 --agent <cmd>` is the JSON-output alias and
   `mem0 init --agent` is the Agent Mode bootstrap flag.

   The Python side already had an argv preprocessor doing the
   equivalent; this brings Node to parity using Commander's built-in
   mechanism (cleaner than mirroring the preprocessor).

   Verified: `mem0 init --agent` with bogus MEM0_BASE_URL now hits the
   bootstrap fetch and surfaces a network error (proving it reached
   bootstrap_via_backend), where before it printed "Non-interactive
   terminal detected" and never made an HTTP call.

2. Both — `config.platform.created_via` was inconsistent: set to
   "agent_mode" / "email" on the agent/claim paths but left empty on
   normal email signup and api-key paths. Now all four paths set it:
   "agent_mode" (bootstrap), "email" (OTP signup or claim), "api_key"
   (--api-key flag or interactive prompt). Downstream consumers can
   reliably filter on created_via==value.

cli/python/src/mem0_cli/commands/init_cmd.py

@@ -284,6 +284,7 @@ def run_init(
         config.platform.api_key = api_key_val
         config.platform.base_url = base_url
         config.platform.user_email = email
+        config.platform.created_via = "email"
         config.defaults.user_id = (
             user_id or os.environ.get("USER") or os.environ.get("USERNAME") or "mem0-cli"
         )
@@ -325,6 +326,7 @@ def run_init(
     # Fully non-interactive when both flags provided
     if api_key and user_id:
         config.platform.api_key = api_key
+        config.platform.created_via = "api_key"
         config.defaults.user_id = user_id
         _validate_platform(config)
         save_config(config)
@@ -365,6 +367,7 @@ def run_init(
             config.platform.api_key = api_key_val
             config.platform.base_url = base_url
             config.platform.user_email = email_addr
+            config.platform.created_via = "email"
             config.defaults.user_id = (
                 user_id or os.environ.get("USER") or os.environ.get("USERNAME") or "mem0-cli"
             )
@@ -383,6 +386,7 @@ def run_init(
     # API key flow
     if api_key:
         config.platform.api_key = api_key
+        config.platform.created_via = "api_key"
     else:
         _setup_platform(config)
 
@@ -422,6 +426,7 @@ def _setup_platform(config: Mem0Config) -> None:
         raise typer.Exit(1)
 
     config.platform.api_key = api_key
+    config.platform.created_via = "api_key"
 
 
 def _setup_defaults(config: Mem0Config) -> None: