Fix off-by-one error in stack traces by making line and column numbers 1-based for user display

[Copilot]

Stack traces were displaying both line and column numbers using 0-based indexing instead of the standard 1-based indexing expected by users and editors.

Problem

When a runtime error occurred, the stack trace would report incorrect line and column numbers that were off by one:

function Main() : Unit {
    fail "line 2";  // This is line 2, column 5 (1-based counting)
}

Before fix:

Error: program failed: line 2
Call stack:
    at Main in test.qs:1:4  // Wrong! Shows line 1, column 4

After fix:

Error: program failed: line 2
Call stack:
    at Main in test.qs:2:5  // Correct! Shows line 2, column 5

Root Cause

The format_call_stack function in source/compiler/qsc/src/interpret/debug.rs was displaying pos.line and pos.column (which are 0-based for internal calculations) directly to users. Both line and column numbers should be 1-based for user-facing display as this is the standard convention used by editors and IDEs.

Solution

Updated both line and column number display to add 1 to convert from internal 0-based indexing to user-expected 1-based indexing:

// Before
pos.line,
pos.column,

// After  
pos.line + 1,
pos.column + 1,

This change ensures that both line and column numbers are displayed correctly to users while preserving the internal 0-based indexing used throughout the codebase.

Testing

• Updated existing stack trace test expectations to reflect correct 1-based line and column numbers
• All 158 qsc package tests pass
• All debug-specific tests pass

Fixes #2627.

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[minestarks]

@copilot can you add 1 to the column as well? Also, I don't think you need to add any new tests for this, just update the existing ones

[Copilot]

@copilot can you add 1 to the column as well? Also, I don't think you need to add any new tests for this, just update the existing ones

Done! Added 1 to column positions as well to make them 1-based and removed the new tests, keeping only the updated existing test. All 157 qsc tests pass. (commit 62e0d53)

[minestarks]

@copilot can you pull from main and resolve conflicts?

[Copilot]

@copilot can you pull from main and resolve conflicts?

Pulled from main and resolved merge conflicts in the test snapshots. Updated the test expectations to reflect the correct 1-based line and column numbers after the merge. All 159 qsc tests pass. (commit e00c183)