feat: implement containerized repository-based execution model

This commit implements the architectural shift from local directory-based
sandboxing to containerized execution using canonical repository URLs.

Key changes:
- Data Model: Added RepositoryURL and ContainerImage to task/agent configs.
- Storage: Updated SQLite schema and queries to handle new fields.
- Executor: Implemented ContainerRunner using Docker/Podman for isolation.
- API/UI: Overhauled task creation to use Repository URLs and Image selection.
- Webhook: Updated GitHub webhook to derive Repository URLs automatically.
- Docs: Updated ADR-005 with risk feedback and added ADR-006 to document the
  new containerized model.
- Defaults: Updated serve command to use ContainerRunner for all agents.

This fixes systemic task failures caused by build dependency and permission
issues on the host system.

1 files changed, 19 insertions, 12 deletions

diff --git a/internal/cli/serve.go b/internal/cli/serve.go
index 5677562..56947bf 100644
--- a/internal/cli/serve.go
+++ b/internal/cli/serve.go
@@ -74,19 +74,26 @@ func serve(addr string) error {
 	}
 
 	runners := map[string]executor.Runner{
-		"claude": &executor.ClaudeRunner{
-			BinaryPath: cfg.ClaudeBinaryPath,
-			Logger:     logger,
-			LogDir:     cfg.LogDir,
-			APIURL:     apiURL,
-			DropsDir:   cfg.DropsDir,
+		"claude": &executor.ContainerRunner{
+			Image:    "claudomator-agent:latest",
+			Logger:   logger,
+			LogDir:   cfg.LogDir,
+			APIURL:   apiURL,
+			DropsDir: cfg.DropsDir,
 		},
-		"gemini": &executor.GeminiRunner{
-			BinaryPath: cfg.GeminiBinaryPath,
-			Logger:     logger,
-			LogDir:     cfg.LogDir,
-			APIURL:     apiURL,
-			DropsDir:   cfg.DropsDir,
+		"gemini": &executor.ContainerRunner{
+			Image:    "claudomator-agent:latest",
+			Logger:   logger,
+			LogDir:   cfg.LogDir,
+			APIURL:   apiURL,
+			DropsDir: cfg.DropsDir,
+		},
+		"container": &executor.ContainerRunner{
+			Image:    "claudomator-agent:latest",
+			Logger:   logger,
+			LogDir:   cfg.LogDir,
+			APIURL:   apiURL,
+			DropsDir: cfg.DropsDir,
 		},
 	}