VS Code extension: line selection metadata is off by one

Description

When selecting a line in VS Code, the Claude Code extension reports the line number in the system-reminder metadata as one less than the actual line. It appears to be sending 0-based line numbers instead of 1-based.

Steps to Reproduce

1. Open a file in VS Code with the Claude Code extension enabled
2. Select/highlight a specific line (e.g., line 137)
3. Send a message to Claude Code referencing the selection
4. Observe the system-reminder says "The user selected the lines 136 to 136"

Expected Behavior

The reported line number should match the 1-based line number shown in the editor. Selecting line 137 should report line 137.

Actual Behavior

The reported line number is consistently off by one (0-based). Selecting line 137 reports line 136. Verified across multiple selections in the same file — always exactly -1.

Environment

• Platform: Linux
• VS Code with Claude Code extension by Anthropic