feat(api): list secrets filter by metadata

[DanielHougaard]

Description 📣

This PR adds support for filtering secrets by their metadata. If multiple metadata fields are passed in, the operation will work as an AND operator, which means the secrets returned will match all the metadata fields.

The format for the secretMetadata query parameter is key1:value1,key2:value2.

The metadata filter is limited to max 10 metadata key-value pairs. This is to avoid overloading the backend, and to avoid bad actors passing into a list with millions of key-value pairs, which could result in a DoS attack.

if (metadata.length > 10) {
                ctx.addIssue({
                  code: z.ZodIssueCode.custom,
                  message: "You can only filter by up to 10 metadata fields"
                });
              }

Type ✨

• Bug fix
• New feature
• Improvement
• Breaking change
• Documentation

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• I have read the contributing guide, agreed and acknowledged the code of conduct. 📝

[akhilmhdh]

All good.

One small thought process was I felt OR would be more appropriate than AND when multiple combo of key=key1,value=value1:key=key2,value=value2

I felt in above [ key1 and value1 ] or [ key2 and value2 ] than [ key1 and value1 ] and [ key2 and value2 ]. But it may be subjective.

CC: @DanielHougaard @maidul98