fix: unlockcode to UUID

[fayekelmith]

Describe your changes

Issue ticket number and link

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist before requesting a review

• I have performed a self-review of my code
• I have tested on Chrome and Firefox
• I have tested on a mobile device
• I have provided a screenshot or recording of changes in my PR if there were updates to the frontend

[Copilot]

Pull Request Overview

This PR updates the unlock code generation mechanism from using the xid library to using UUID (Universally Unique Identifier). The change addresses potential collision risks by switching to a more robust identifier format.

Key Changes:

• Replaced xid library with standard uuid package for unlock code generation
• Updated database schema to accommodate longer UUID strings (36 characters vs 6)

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
handlers/bounty.go	Removed xid dependency and updated generateUnlockCode() to return UUID strings
db/structs.go	Increased UnlockCode field length from 6 to 36 characters in both Bounty and NewBounty structs

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[Copilot]

This schema change from varchar(6) to varchar(36) requires a database migration. Ensure that a migration script is included to alter existing database columns, otherwise existing deployments will fail when writing UUID values to the shorter column.

Suggested change

	AccessRestriction *AccessRestrictionType `gorm:"type:varchar(20);default:null" json:"access_restriction,omitempty"`
	AccessRestriction *AccessRestrictionType `gorm:"type:varchar(20);default:null" json:"access_restriction,omitempty"`
	// NOTE: If upgrading from a previous schema where unlock_code was varchar(6), you MUST run the following migration:
	// ALTER TABLE bounties ALTER COLUMN unlock_code TYPE varchar(36);

[Evanfeenstra]

just do 6 random lowercase/uppercase letters. that would work right?

[Evanfeenstra]

const letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

func GenerateRandomCode(length int) string {
    result := make([]byte, length)
    for i := range result {
        result[i] = letters[rand.Intn(len(letters))]
    }
    return string(result)
}

[Evanfeenstra]

and js:

function generateRandomCode(length = 6) {
    const letters = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    const randomValues = new Uint8Array(length);
    crypto.getRandomValues(randomValues);
    
    return Array.from(randomValues)
        .map(x => letters[x % letters.length])
        .join('');
}

[Evanfeenstra]

it needs to be 6 since its varchar(6)