Add triggershell run/scripts - execute configured scripts from the CLI

`run <scriptId>` auto-detects whether the web server is already
reachable (a quick /api/healthz check):

- If it is, the run goes through the existing POST
  /api/scripts/:id/runs endpoint (token-authenticated, same as any
  other API client) and the CLI subscribes over /ws/runs exactly like
  a browser tab - so the run shows up live in Run History and any open
  browser watching it, with zero server-side changes, since the
  broadcast path has no idea a run was triggered by a click vs a CLI
  invocation.
- If nothing's reachable, it calls startRun() directly in its own
  process (after its own migrateOnBoot/reconcileOrphanedRuns, so a
  from-scratch .triggershell/ works standalone) and streams output by
  listening on the same in-process runEvents emitter a WS client would
  otherwise be fed from - read-log-then-listen, the same ordering
  ws/server.ts's subscribe() already uses, so a fast script finishing
  before the listener attaches still gets its output printed.

Both modes support --var name=value (repeatable; repeat a name for
multiselect), --no-wait, and Ctrl-C cancellation through the same
mechanism the web UI's Cancel button uses (a WS cancel message
remotely, cancelRun() directly locally). `scripts list`/`scripts show`
are local-only, no network - same direct-config-read pattern as
`validate`/`doctor`.

Extracts defaultValuesForScript() out of dynamic-form.tsx into
src/lib/config/defaults.ts so the CLI's --var handling and the web
form fill in a script's configured defaults identically instead of
duplicating that logic.

Verified live end-to-end: a CLI-triggered remote run was observed
streaming to both the triggering CLI process and an independent WS
client (simulating a browser tab) simultaneously; local-mode Ctrl-C
confirmed to actually kill the spawned child process, not just the
CLI; token, wrong-token, and TRIGGERSHELL_API_TOKEN auth paths all
verified against a running auth-enabled server.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/components/forms/dynamic-form.tsx

@@ -10,30 +10,23 @@ import { Button } from "@/components/ui/button";
 import { Form } from "@/components/ui/form";
 import { Alert, AlertDescription } from "@/components/ui/alert";
 import { buildVariableSchemaFromList } from "@/lib/validation/variable-schema";
+import { defaultValuesForScript } from "@/lib/config/defaults";
 import type { ClientScript } from "@/lib/config/serialize";
 import { FieldRenderer } from "./field-renderer";
 
-function emptyValueFor(variable: ClientScript["variables"][number]): unknown {
-  if (variable.type === "boolean") return false;
-  if (variable.type === "multiselect") return [];
-  return "";
-}
-
 /** `initialValues` comes from a previous run's (already-redacted) variables when re-running -
  * secret fields are deliberately excluded there (their stored value is just "***", not the real
- * one), so those always fall through to the normal empty/default state and have to be re-entered. */
+ * one), so those always fall through to the normal default/empty state and have to be re-entered. */
 function defaultValuesFor(
   script: ClientScript,
   initialValues?: Record<string, unknown>,
 ): Record<string, unknown> {
-  const values: Record<string, unknown> = {};
+  const values = defaultValuesForScript(script.variables);
+  if (!initialValues) return values;
   for (const variable of script.variables) {
-    const fromPreviousRun =
-      initialValues && !variable.secret
-        ? initialValues[variable.name]
-        : undefined;
-    values[variable.name] =
-      fromPreviousRun ?? variable.default ?? emptyValueFor(variable);
+    if (variable.secret) continue;
+    const fromPreviousRun = initialValues[variable.name];
+    if (fromPreviousRun !== undefined) values[variable.name] = fromPreviousRun;
   }
   return values;
 }