refactor: prefix all manifest data classes with Manifest

Avoids name collisions with same-named runtime/plugin classes
(e.g. manifest AgentProvider vs plugin AgentProvider ABC,
manifest EgressRoute vs runtime EgressRoute). Renamed:

  AgentProvider        → ManifestAgentProvider   (manifest_agent.py)
  Agent                → ManifestAgent            (manifest_agent.py)
  EgressRoute          → ManifestEgressRoute      (manifest_egress.py)
  PathMatch            → ManifestPathMatch        (manifest_egress.py)
  HeaderMatch          → ManifestHeaderMatch      (manifest_egress.py)
  MatchEntry           → ManifestMatchEntry       (manifest_egress.py)
  EgressConfig         → ManifestEgressConfig     (manifest_egress.py)
  Bottle               → ManifestBottle           (manifest.py)
  ProvisionedKeyConfig → ManifestProvisionedKeyConfig (manifest_git.py)
  GitEntry             → ManifestGitEntry         (manifest_git.py)
  GitUser              → ManifestGitUser          (manifest_git.py)

tests/unit/test_manifest_runtime.py

@@ -7,7 +7,7 @@ silently ignoring."""
 import unittest
 from typing import Any
 
-from bot_bottle.manifest import ManifestError, Bottle, Manifest
+from bot_bottle.manifest import ManifestError, ManifestBottle, Manifest
 
 
 def _manifest_with_runtime(value: object) -> dict[str, Any]:
@@ -26,7 +26,7 @@ class TestManifestRuntimeRemoved(unittest.TestCase):
         self.assertIn("dev", m.bottles)
 
     def test_bottle_dataclass_has_no_runtime_attribute(self):
-        self.assertFalse(hasattr(Bottle(), "runtime"))
+        self.assertFalse(hasattr(ManifestBottle(), "runtime"))
 
     def test_any_runtime_value_is_rejected(self):
         for value in ("runsc", "runc", "kata-runtime", "", 42, None):