fix: get-pr-context scripts resolve REPO_ROOT incorrectly after deployment

Scripts live 2 levels deep in source (scripts/bash/, scripts/powershell/)
but are deployed 3 levels deep (.documentation/scripts/bash/, .documentation/scripts/powershell/).
The hardcoded '../..' resolved to .documentation/ instead of the repo root.

Both scripts now use `git rev-parse --show-toplevel` first (always correct),
with a 3-level-up directory fallback for non-git environments — matching the
pattern already used by common.sh/common.ps1.

The PowerShell script's $repoRoot is now a plain string (matching Get-RepoRoot
in common.ps1), so three $repoRoot.Path references are updated to $repoRoot.

Agent-Logs-Url: https://github.com/markhazleton/spec-kit/sessions/68e9588e-12f7-4aaa-91fd-6c14def251d3

Co-authored-by: markhazleton <223906+markhazleton@users.noreply.github.com>

Author: Copilot

scripts/bash/get-pr-context.sh

@@ -18,7 +18,11 @@ set -o pipefail
 #==============================================================================
 
 SCRIPT_DIR="$(CDPATH="" cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-REPO_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)"
+if git rev-parse --show-toplevel >/dev/null 2>&1; then
+    REPO_ROOT="$(git rev-parse --show-toplevel)"
+else
+    REPO_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"
+fi
 
 PR_NUMBER=""
 JSON_MODE=false

scripts/powershell/get-pr-context.ps1

@@ -32,7 +32,12 @@ $ErrorActionPreference = "Stop"
 #==============================================================================
 
 $scriptPath = Split-Path -Parent $MyInvocation.MyCommand.Path
-$repoRoot = (Resolve-Path "$scriptPath\..\..")
+$gitRoot = try { git rev-parse --show-toplevel 2>$null } catch { $null }
+if ($LASTEXITCODE -eq 0 -and $gitRoot) {
+    $repoRoot = $gitRoot.Trim()
+} else {
+    $repoRoot = (Resolve-Path "$scriptPath\..\..\..\").Path
+}
 
 #==============================================================================
 # Utility Functions
@@ -170,16 +175,16 @@ if (-not $IncludeAllFiles -and $filesChangedTotal -gt $FileSampleLimit) {
 }
 
 # Check for constitution
-$constitutionPath = Join-Path $repoRoot.Path ".documentation\memory\constitution.md"
+$constitutionPath = Join-Path $repoRoot ".documentation\memory\constitution.md"
 $constitutionExists = Test-Path $constitutionPath
 
 # Prepare review directory
-$reviewDir = Join-Path $repoRoot.Path ".documentation\specs\pr-review"
+$reviewDir = Join-Path $repoRoot ".documentation\specs\pr-review"
 
 # Build output
 if ($Json) {
     $output = @{
-        REPO_ROOT = $repoRoot.Path
+        REPO_ROOT = $repoRoot
         PR_CONTEXT = @{
             enabled = $true
             pr_number = $prData.number