refactor(web): remove the create-task modal from the UI (Phase 3)

The observability UI no longer creates tasks; chatbots do that via the chatbot
MCP server. Removes the New Task button, the #task-modal (manual form + the
now-defunct AI-elaborate textbox + validate panel), their handlers
(elaborateTask/validateTask/buildValidatePayload/renderValidationResult/
openTaskModal/closeTaskModal/createTask) and the orphaned
newTaskButtonShouldShowOnTab helper plus its test.

Verified with node --test (267 JS tests pass) and a JS syntax check. Not
browser-verified in this environment.

https://claude.ai/code/session_01SESwn7kQ7oP62trWw6pc39

1 files changed, 0 insertions, 24 deletions

diff --git a/web/test/new-task-button.test.mjs b/web/test/new-task-button.test.mjs
deleted file mode 100644
index 45a3548..0000000
--- a/web/test/new-task-button.test.mjs
+++ /dev/null
@@ -1,24 +0,0 @@
-// new-task-button.test.mjs — visibility contract for the New Task button
-//
-// The New Task button lives in the global header and must be visible on all tabs.
-// Run with: node --test web/test/new-task-button.test.mjs
-
-import { describe, it } from 'node:test';
-import assert from 'node:assert/strict';
-import { newTaskButtonShouldShowOnTab } from '../app.js';
-
-const ALL_TABS = ['tasks', 'active', 'running', 'stats'];
-
-describe('new task button visibility', () => {
-  for (const tab of ALL_TABS) {
-    it(`is visible on "${tab}" tab`, () => {
-      assert.equal(newTaskButtonShouldShowOnTab(tab), true, `expected button to be visible on tab "${tab}"`);
-    });
-  }
-
-  it('is visible on any unknown future tab', () => {
-    assert.equal(newTaskButtonShouldShowOnTab('help'), true);
-    assert.equal(newTaskButtonShouldShowOnTab('templates'), true);
-    assert.equal(newTaskButtonShouldShowOnTab(''), true);
-  });
-});