feat: update docs

[RohitKushvaha01]

Updated the docs using ai

[greptile-apps]

Greptile Summary

The PR substantially expands and reorganizes the plugin-development documentation.

• Adds dedicated documentation for Executor, System, Config, and Plugin Context APIs.
• Updates plugin lifecycle examples to follow the class-based template.
• Documents manifest permissions and adds the new pages to VitePress navigation.
• Consolidates terminal background-execution guidance under the new Executor page.

Confidence Score: 5/5

The PR appears safe to merge because no blocking failure remains in the eligible follow-up review scope.

No blocking failure remains.

Important Files Changed

Filename	Overview
docs/advanced-apis/executor.md	Adds comprehensive documentation for one-off, streaming, and background process execution.
docs/advanced-apis/system.md	Adds a broad reference for the native Android system bridge and its callback-based APIs.
docs/getting-started/understanding-plugin.md	Replaces the procedural lifecycle example with the class-based plugin template and documents context forwarding.
docs/global-apis/config.md	Adds a reference for the read-only application configuration module and its exposed constants.
docs/plugin-essentials/core-file.md	Expands initialization arguments and updates the core-file example and cleanup guidance.
docs/plugin-essentials/manifest.md	Documents the manifest permissions array and its relationship to plugin context.
docs/plugin-essentials/plugin-context.md	Adds documentation for plugin-scoped secret storage, permission checks, and context metadata.
.vitepress/config.mts	Adds the new Plugin Context, Config, Executor, and System pages to site navigation.

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