Fix RPM multi-version installation support using versioned directories and update-alternatives (#12610)

[Ronitsabhaya75]

Fixes #12610 - RPM multi-version installation conflicts

Problem

Installing multiple FoundationDB client versions on RPM systems fails with file conflicts:

 file /usr/bin/fdbcli from install of foundationdb-clients-7.1.65 
conflicts with file from package foundationdb-clients-6.3.23

Both versions try to install to the same paths, preventing multi-version client API usage.

Solution
Modified RPM packaging to use versioned directories and update-alternatives for symlink management:

buildrpms.sh: Install to /usr/lib/foundationdb-{VERSION}/ instead of /usr/bin/, /usr/lib64/
foundationdb.spec.in: Use update-alternatives to manage symlinks from standard paths to versioned binaries
Example:

# Version 6.3.23 installs to: /usr/lib/foundationdb-6.3.23/
# Version 7.1.65 installs to: /usr/lib/foundationdb-7.1.65/
# Symlink managed: /usr/bin/fdbcli -> /usr/lib/foundationdb-7.1.65/bin/fdbcli

Multiple versions now coexist. Users can switch with update-alternatives --config fdbcli.

Backwards Compatibility
Standard paths (/usr/bin/fdbcli, /usr/lib64/libfdb_c.so) maintained via symlinks. Existing scripts continue to work.

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@xis19 @vishesh can you please review this change for the issue

[foundationdb-ci]

Result of foundationdb-pr-clang-ide on Linux RHEL 9

• Commit ID: e7e7876
• Duration 0:36:46
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-clang-arm on Linux CentOS 7

• Commit ID: e7e7876
• Duration 0:42:56
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-clang on Linux RHEL 9

• Commit ID: e7e7876
• Duration 1:17:24
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr on Linux RHEL 9

• Commit ID: e7e7876
• Duration 1:21:08
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)

[foundationdb-ci]

Result of foundationdb-pr-cluster-tests on Linux RHEL 9

• Commit ID: e7e7876
• Duration 2:07:16
• Result: ✅ SUCCEEDED
• Error: N/A
• Build Log terminal output (available for 30 days)
• Build Workspace zip file of the working directory (available for 30 days)
• Cluster Test Logs zip file of the test logs (available for 30 days)

[Ronitsabhaya75]

@jzhou77 can we merge this its been approved by both reviewers and CI

[jzhou77]

@jzhou77 can we merge this its been approved by both reviewers and CI

@Ronitsabhaya75 thanks for the fix! Can you describe if you have tested the fix? Ideally, we want to port the PR to 7.3 or 7.4, create RPMs and do an upgrade test to verify it works as intended. I am also aware that building RPMs takes a lot of machine time, especially if you don't have big machines.

So if you have done the test, I'd be happy to merge this PR. Otherwise, it's better we wait until someone in the team has test it before merging.

[Ronitsabhaya75]

@jzhou77 can we merge this its been approved by both reviewers and CI

@Ronitsabhaya75 thanks for the fix! Can you describe if you have tested the fix? Ideally, we want to port the PR to 7.3 or 7.4, create RPMs and do an upgrade test to verify it works as intended. I am also aware that building RPMs takes a lot of machine time, especially if you don't have big machines.

So if you have done the test, I'd be happy to merge this PR. Otherwise, it's better we wait until someone in the team has test it before merging.

@jzhou77 I agree I havent tested the fix but im pretty sure it will be good. I'd wait for until someone test it before release. Looking for feedback. thank you so much