Add the Google Ads plugin (Grok Bot, REST MCP)

[ericgyl817]

• What: adds third_party/google-ads (Grok Bot only, cursor: never) pointing at https://api.cursor.com/rest-mcp/google-ads/mcp, the 16-tool Google Ads translator from everysphere #1143810, plus its marketplace and README rows.
• Why: Google Ads joins Drive, Sheets, Calendar and Gmail as an official plugin instead of a URL users paste.
• Hold: merge after Google verifies the adwords scope on the Grok OAuth project (313336824172); until then users outside the project hit the unverified-app screen and its 100-user cap.

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Note

Medium Risk
The plugin enables OAuth access to Google Ads accounts and documented mutate tools; rollout still depends on Google verifying the OAuth app (unverified cap noted in the PR).

Overview
Adds a new google-ads third-party plugin so Grok Bot can use Google Ads through Cursor’s hosted REST MCP instead of a manual MCP URL.

The package wires mcp.json to https://api.cursor.com/rest-mcp/google-ads/mcp, ships manifest/docs/changelog/logo/MIT license, and sets cursor: "never" (Grok Bot / Sand ≥ 0.30.0 only). .cursor-plugin/marketplace.json and the root README plugin table list it under Integrations with the same one-line description.

Documented behavior: OAuth with the adwords scope, GAQL reporting and planning tools, and campaign writes gated by validate_mutate before mutate.

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