Enterprise sign-in fast path, MCP OAuth metadata documents, /context scrolling, and markdown agent…

Fast return path for enterprise sign-in, support for OAuth client ID metadata documents in MCP servers, terminal-sized scrollable /context and /usage panels, unified inheritCustomizations configuration for markdown agents, read-only permissions outside the workspace, and fixes for language server crashes, hyperlink rendering, artifact approval tracking, MCP error isolation, and bracketed paste.

• Added a faster return path for enterprise sign-in, offering returning users a single Continue with... option naming the authentication method they last used.
• Added support for OAuth client ID metadata documents when connecting to an MCP server, allowing servers implementing this specification to connect without requiring a manually supplied client ID or dynamic client registration.
• Improved the /context panel, making it scrollable and dynamically sized to the terminal, with /usage sized the same way.
• Improved markdown-defined agents with a single inheritCustomizations switch that controls whether an agent adopts skills, rules, plugins, subagents, and MCP servers, replacing inconsistent per-kind defaults.
• Improved workspace boundary settings: accessing paths outside the workspace now grants read access only, with writes requiring authorization based on the active execution mode.
• Fixed the CLI exiting silently when its language server failed at startup or during execution; failures are now logged to the terminal and exit with a non-zero status.
• Fixed sign-in URLs and hyperlinks rendering as garbled escape sequences on terminals that do not support OSC 8 hyperlinks (such as GNU screen), detecting unsupported terminals and rendering plain text instead.
• Fixed Enter keystrokes being swallowed while the path-suggestion popup was loading, which previously sent the prompt and popped results open above it.
• Fixed the artifact list marking previously unreviewed, commented, or rejected artifacts as approved when reopening the list.
• Fixed malformed MCP server configurations causing all other servers to fail; invalid entries are now logged and skipped while remaining servers continue loading.
• Fixed built-in skills, rules, and plugins being stripped when an agent configured inherit_user: false, ensuring built-in capabilities remain available while personal customizations are excluded.
• Fixed conversation branching and rollbacks failing with too many SQL variables on long trajectories.
• Fixed conversation titles unexpectedly jumping to older messages after trajectory truncation by protecting the title checkpoint.
• Fixed multi-line pastes submitting individual prompts per line on terminals that do not support bracketed paste.