refactor(manifest): convert TypedDict to frozen dataclasses

Replace the TypedDict + 14 manifest_* free functions with frozen
dataclasses (SshEntry, BottleEgress, Bottle, Agent, Manifest) carrying
their own validators and constructors. Call sites import Manifest and
chain attribute access; the manifest_* helpers and manifest_validate
are gone.

Behavior changes worth flagging:
- Agent.bottle is now required (was optional with a "(none)" fallback).
  Manifest.from_json_obj dies if any agent lacks a 'bottle' field or
  references an undefined bottle, where previously start.py raised the
  error lazily for the specific agent being launched.
- ssh.py now takes SshEntry instances; Host/IdentityFile shape checks
  moved upstream into Manifest construction, leaving only the IdentityFile
  filesystem-existence check in ssh_validate_entries.
- pipelock_bottle_allowlist's per-element string check is dropped — the
  Manifest validator enforces it at load.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

claude_bottle/cli/list.py

@@ -7,7 +7,7 @@ import subprocess
 
 from .. import docker as docker_mod
 from ..log import info
-from ..manifest import manifest_resolve
+from ..manifest import Manifest
 from ._common import PROG, USER_CWD
 
 
@@ -17,8 +17,8 @@ def cmd_list(argv: list[str]) -> int:
     args = parser.parse_args(argv)
 
     if args.scope == "available":
-        manifest = manifest_resolve(USER_CWD)
-        for name in (manifest.get("agents") or {}).keys():
+        manifest = Manifest.resolve(USER_CWD)
+        for name in manifest.agents.keys():
             print(name)
         return 0