refactor: remove unreachable runner code (#1179)

Remove inherited act APIs, configuration branches, and test seams that neither the daemon nor exec can reach. Constant-fold settings both entry points already enforce and consolidate duplicate runner paths.

Major removals:

- Unwired custom action-cache and local-repository-cache implementations.
- Legacy matrix, platform, input, container-reuse, logging, Git remote, and action-replacement configuration paths.
- Unused Docker socket, container network, tar-copy, and platform PTY wrappers.
- Single-implementation filesystem, environment, runner, and expression abstractions.
- Duplicated step-container, command-logging, credential, reusable-workflow, and execution paths.
- Generated client mock boilerplate, obsolete fixtures, test-only seams, stale wrappers, and commented-out code.

This removes 2844 net Go lines while retaining Gitea RPC, event, matrix, input, cache, artifact, action, reusable workflow, Docker, host, exec, and release behavior.

Assisted by Codex (GPT-5).

Reviewed-on: https://gitea.com/gitea/runner/pulls/1179
Reviewed-by: bircni <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>

act/common/executor.go

@@ -54,22 +54,6 @@ func NewPipelineExecutor(executors ...Executor) Executor {
 	return rtn
 }
 
-// NewConditionalExecutor creates a new executor based on conditions
-func NewConditionalExecutor(conditional Conditional, trueExecutor, falseExecutor Executor) Executor {
-	return func(ctx context.Context) error {
-		if conditional(ctx) {
-			if trueExecutor != nil {
-				return trueExecutor(ctx)
-			}
-		} else {
-			if falseExecutor != nil {
-				return falseExecutor(ctx)
-			}
-		}
-		return nil
-	}
-}
-
 // NewErrorExecutor creates a new executor that always errors out
 func NewErrorExecutor(err error) Executor {
 	return func(ctx context.Context) error {
@@ -192,10 +176,3 @@ func (e Executor) Finally(finally Executor) Executor {
 		return err
 	}
 }
-
-// Not return an inverted conditional
-func (c Conditional) Not() Conditional {
-	return func(ctx context.Context) bool {
-		return !c(ctx)
-	}
-}