Add permission modes and container introspection backend

Permission modes: replaces the binary full_permissions flag with a
PermissionMode enum (Plan/Default/AcceptEdits/Bypass). Flag mapping is
defined once in PermissionMode::cli_args() and used by the terminal, the
web terminal, and the scheduler:
  Plan        -> --permission-mode plan
  Default     -> (no flag)
  AcceptEdits -> --permission-mode acceptEdits
  Bypass      -> --dangerously-skip-permissions
Choices verified against `claude --permission-mode` on 2.1.226.

full_permissions is retained and effective_permission_mode() falls back
to it, so existing projects.json needs no migration.

Bug fix: triple-c-task-runner ran `claude -p ... --dangerously-skip-
permissions` unconditionally, ignoring the project's setting entirely.
It now reads TRIPLE_C_PERMISSION_MODE, which is injected into the
container, added to the reserved env blocklist, propagated through the
entrypoint's cron env filter, and tracked by a new
triple-c.permission-mode label so a change forces recreation.

Introspection: new commands/inspect_commands.rs exposes read-only views
into the container over docker exec — Claude sessions (parsed from
~/.claude/projects/<cwd>/<uuid>.jsonl), installed capabilities (skills,
agents, commands, hooks, plugins, natively-configured MCP servers), and
the triple-c-scheduler task list, logs and notifications.

Task/session ids are validated against a strict allowlist and every
parameterized call runs as a bare argv vector via bollard, so no shell
is involved. Stopped containers return empty results rather than errors.

No UI yet; that lands with the Project Home view.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

container/entrypoint.sh

@@ -255,7 +255,7 @@ ENV_FILE="$SCHEDULER_DIR/.env"
 : > "$ENV_FILE"
 env | while IFS='=' read -r key value; do
     case "$key" in
-        ANTHROPIC_*|AWS_*|CLAUDE_CODE_*|PATH|HOME|LANG|TZ|COLORTERM)
+        ANTHROPIC_*|AWS_*|CLAUDE_CODE_*|TRIPLE_C_PERMISSION_MODE|PATH|HOME|LANG|TZ|COLORTERM)
             # Escape single quotes in value and write as KEY='VALUE'
             escaped_value=$(printf '%s' "$value" | sed "s/'/'\\\\''/g")
             printf "%s='%s'\n" "$key" "$escaped_value" >> "$ENV_FILE"