feat: make install.sh configurable for air-gapped environments

[chkp-roniz]

Summary

• APM_INSTALL_DIR env var to override install path (default /usr/local/bin)
• GITHUB_URL env var to override GitHub base URL for mirrors/GHE
• REPO env var to override repository (default microsoft/apm)
• VERSION env var or @v1.2.3 arg to pin a specific version — skips GitHub API entirely when set

Usage

# Specific version (no GitHub API call needed)
curl -sSL https://aka.ms/apm-unix | sh -s -- @v0.8.10

# Custom install directory
curl -sSL https://aka.ms/apm-unix | APM_INSTALL_DIR=~/.local/bin sh

# Air-gapped / internal mirror
GITHUB_URL=https://artifactory.corp.com/artifactory/github VERSION=v0.8.10 sh install.sh

Test plan

• Tested with custom GITHUB_URL + VERSION=v0.8.10 — downloads from mirror, skips API
• Tested with unreachable API — confirmed API is skipped when VERSION is set
• Tested with APM_INSTALL_DIR=$HOME/.local/bin — installs to custom dir without sudo
• bash -n install.sh syntax check passes
• No hardcoded https://github.com outside Configuration defaults

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates the install.sh bootstrap installer to support air-gapped and enterprise environments by allowing callers to override the GitHub host/repo, install location, and (optionally) pin a version to avoid the GitHub API.

Changes:

• Added configurable environment variables: APM_INSTALL_DIR, GITHUB_URL, REPO, and VERSION (plus @vX.Y.Z positional argument support).
• When VERSION is provided, the installer skips the GitHub API and constructs the release download URL directly.
• Updated user-facing URLs/messages to use the configurable GitHub base URL.

Comments suppressed due to low confidence (3)

install.sh:224

• GITHUB_URL is configurable, but the script still hardcodes https://api.github.com/... for the latest release lookup. This will break GitHub Enterprise / mirrored setups when VERSION is not provided, and it also conflicts with the PR description mentioning GITHUB_API_URL. Consider adding a GITHUB_API_URL (defaulting to https://api.github.com, or derived from GITHUB_URL) and using it for both unauthenticated and authenticated API calls.

if [ -z "$TAG_NAME" ]; then
# Get latest release info
echo -e "${YELLOW}Fetching latest release information...${NC}"

# Try to fetch release info without authentication first (for public repos)
LATEST_RELEASE=$(curl -s "https://api.github.com/repos/$REPO/releases/latest")
CURL_EXIT_CODE=$?

install.sh:518

• Output strings in this modified block include non-ASCII characters (e.g., ✓, ⚠, 🎉). The repo encoding guideline requires printable ASCII only for source/CLI output; please replace these with the project's ASCII status symbols (e.g. [+], [!]) to avoid Windows cp1252 UnicodeEncodeError issues.

    echo -e "${GREEN}✓ APM installed successfully!${NC}"
    echo -e "${BLUE}Version: $INSTALLED_VERSION${NC}"
    echo -e "${BLUE}Location: $APM_INSTALL_DIR/$BINARY_NAME -> $APM_LIB_DIR/$BINARY_NAME${NC}"
else
    echo -e "${YELLOW}⚠ APM installed but not found in PATH${NC}"
    echo "You may need to add $APM_INSTALL_DIR to your PATH environment variable."
    echo "Add this line to your shell profile (.bashrc, .zshrc, etc.):"
    echo "  export PATH=\"$APM_INSTALL_DIR:\$PATH\""
fi

echo ""
echo -e "${GREEN}🎉 Installation complete!${NC}"

install.sh:12

• The private-repo usage example still hardcodes https://raw.githubusercontent.com/microsoft/apm/... even though REPO/GITHUB_URL are now configurable for GHE/mirrors. Consider either updating these instructions to match the new configuration knobs (or explicitly documenting that these curl examples apply only to github.com).

# For private repositories, use with authentication:
#   curl -sSL -H "Authorization: token $GITHUB_APM_PAT" \
#     https://raw.githubusercontent.com/microsoft/apm/main/install.sh | \
#     GITHUB_APM_PAT=$GITHUB_APM_PAT sh

[Copilot]

This change introduces new supported installer inputs (APM_INSTALL_DIR, GITHUB_URL, REPO, VERSION / @vX.Y.Z). The repo docs currently describe a fixed /usr/local/bin install path and don't mention version pinning or air-gapped/GHE usage (e.g. docs/src/content/docs/getting-started/installation.md). Please update the relevant docs pages (and the apm-guide skill docs under packages/apm-guide/.apm/skills/apm-usage/) to reflect the new options.