Split examples into v0 and v1

[rahulshendre]

What this PR does:
Restructures the examples/ directory into v0/ and v1/ subdirectories. All the current examples move under v0/, and I added a v1/ directory for the upcoming PipeCD v1 (plugin architecture) examples. The shared README.remote.md at the root now points to both, and the existing catalog moved into v0/README.md.

Why we need it:
Start of adding v1 examples and a lot of users still reference the v0 ones, so we keep both side by side instead of replacing them.

Which issue(s) this PR fixes:

Related to #6266

Does this PR introduce a user-facing change?:

• How are users affected by this change:
• Is this breaking change:
• How to migrate (if breaking change):

[aamirpatel]

Reviewed

[armistcxy]

agree, split them to avoid confuse

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[armistcxy]

@rahulshendre test fail due to moving examples, I think you should update the test also

Suggestion from Copilot when explaining action error

[armistcxy]

I think we need to update docs/content/en/docs-dev/examples/_index.md also @rahulshendre

[rahulshendre]

I think we need to update docs/content/en/docs-dev/examples/_index.md also @rahulshendre

thanks for the mention, @armistcxy. those links will need updating, they point to the separate pipe-cd/examples repo (not the examples/ dir here), so they still resolve fine today and would only break if I switch them to v0/ before that repo is restructured. Per #6266 we're restructuring pipe-cd/examples the same way, and I'll update index.md to v0/ as part of that.
I was thinking of keeping this PR scoped to the main-repo move, what do you think 👀

[rahulshendre]

@rahulshendre test fail due to moving examples, I think you should update the test also

Thanks @armistcxy, nice catch. That test hardcodes the old examples/kubernetes/simple path, so the move to examples/v0/ broke it. I've updated both paths in sync_test.go to point at examples/v0/. PTAL

[armistcxy]

I was thinking of keeping this PR scoped to the main-repo move, what do you think 👀

Agree, thanks for pointing out those links belong to another repo

[rahulshendre]

@khanhtc1202 @mohammedfirdouss, PTAL when you have time