refactor(read_file): Codex-inspired read_file refactor

[hannesrudolph]

What This Means for Users

Simplified Configuration

Two settings removed from Settings UI:

• Max File Read Lines - You no longer need to configure a global line limit. The agent now reads what it needs intelligently.
• Max Concurrent File Reads - This setting is no longer used and has been cleaned up.

Smarter File Reading

The read_file tool now uses indentation-aware reading that understands code structure:

• When reading a function, method, or class, the agent automatically includes the complete logical block
• Sibling context (nearby functions/methods at the same indentation level) is included for better understanding
• No more truncated code blocks that cut off mid-function

Per-Request Control

Instead of a global setting, the agent can now specify limits per request when needed:

• Most reads use smart defaults with no limit
• When appropriate, specific calls can request limited output
• This eliminates the need for users to guess at "good" global values

What Changed Technically

• read_file tool redesigned to use single-file API with indentation mode (adapted from Codex CLI)
• Removed maxReadFileLine global setting (replaced by per-call limit parameter)
• Removed unused maxConcurrentFileReads setting and plumbing
• Cleaned up related dead code from system prompts and state management

Breaking Changes

• Users who had customized maxReadFileLine will need to rely on the new intelligent defaults
• The setting will no longer appear in exported configurations

[roomote]

Oroocle   See task on Roo Cloud

Re-review complete. No new issues found in the latest commit.

• read_file: wire up indentation.max_lines through nativeArgs parsing so it reaches the tool implementation

Previous reviews

• afa6cf9: Review #1
• f070c84: Review #2
• 3770f2e: Review #3

_{Mention @roomote in a comment to request specific changes to this pull request or fix all unresolved issues.}