refactor(hashline): override native edit tool instead of separate tool + disabler hook

Replace 3-component hashline system (separate hashline_edit tool + edit
disabler hook + OpenAI-exempted read enhancer) with 2-component system
that directly overrides the native edit tool key, matching the
delegate_task pattern.

- Register hashline tool as 'edit' key to override native edit
- Delete hashline-edit-disabler hook (no longer needed)
- Delete hashline-provider-state module (no remaining consumers)
- Remove OpenAI exemption from read enhancer (explicit opt-in means all providers)
- Remove setProvider wiring from chat-params

src/plugin/chat-params.ts

@@ -1,5 +1,3 @@
-import { setProvider } from "../features/hashline-provider-state"
-
 type ChatParamsInput = {
   sessionID: string
   agent: { name?: string }
@@ -68,8 +66,6 @@ export function createChatParamsHandler(args: {
     if (!normalizedInput) return
     if (!isChatParamsOutput(output)) return
 
-    setProvider(normalizedInput.sessionID, normalizedInput.model.providerID)
-
     await args.anthropicEffort?.["chat.params"]?.(normalizedInput, output)
   }
 }

src/plugin/hooks/create-tool-guard-hooks.ts

@@ -10,7 +10,6 @@ import {
   createRulesInjectorHook,
   createTasksTodowriteDisablerHook,
   createWriteExistingFileGuardHook,
-  createHashlineEditDisablerHook,
   createHashlineReadEnhancerHook,
 } from "../../hooks"
 import {
@@ -30,7 +29,6 @@ export type ToolGuardHooks = {
   rulesInjector: ReturnType<typeof createRulesInjectorHook> | null
   tasksTodowriteDisabler: ReturnType<typeof createTasksTodowriteDisablerHook> | null
   writeExistingFileGuard: ReturnType<typeof createWriteExistingFileGuardHook> | null
-  hashlineEditDisabler: ReturnType<typeof createHashlineEditDisablerHook> | null
   hashlineReadEnhancer: ReturnType<typeof createHashlineReadEnhancerHook> | null
 }
 
@@ -89,10 +87,6 @@ export function createToolGuardHooks(args: {
     ? safeHook("write-existing-file-guard", () => createWriteExistingFileGuardHook(ctx))
     : null
 
-  const hashlineEditDisabler = isHookEnabled("hashline-edit-disabler")
-    ? safeHook("hashline-edit-disabler", () => createHashlineEditDisablerHook(pluginConfig))
-    : null
-
   const hashlineReadEnhancer = isHookEnabled("hashline-read-enhancer")
     ? safeHook("hashline-read-enhancer", () => createHashlineReadEnhancerHook(ctx, { hashline_edit: { enabled: pluginConfig.experimental?.hashline_edit ?? false } }))
     : null
@@ -106,7 +100,6 @@ export function createToolGuardHooks(args: {
     rulesInjector,
     tasksTodowriteDisabler,
     writeExistingFileGuard,
-    hashlineEditDisabler,
     hashlineReadEnhancer,
   }
 }

src/plugin/tool-execute-before.ts

@@ -29,8 +29,6 @@ export function createToolExecuteBeforeHandler(args: {
     await hooks.prometheusMdOnly?.["tool.execute.before"]?.(input, output)
     await hooks.sisyphusJuniorNotepad?.["tool.execute.before"]?.(input, output)
     await hooks.atlasHook?.["tool.execute.before"]?.(input, output)
-    await hooks.hashlineEditDisabler?.["tool.execute.before"]?.(input, output)
-
     if (input.tool === "task") {
       const argsObject = output.args
       const category = typeof argsObject.category === "string" ? argsObject.category : undefined

src/plugin/tool-registry.ts

@@ -120,7 +120,7 @@ export function createToolRegistry(args: {
 
   const hashlineEnabled = pluginConfig.experimental?.hashline_edit ?? false
   const hashlineToolsRecord: Record<string, ToolDefinition> = hashlineEnabled
-    ? { hashline_edit: createHashlineEditTool() }
+    ? { edit: createHashlineEditTool() }
     : {}
 
   const allTools: Record<string, ToolDefinition> = {