Remove SourceField mode

[Xtansia]

Description

Removed unsupported _common.mapping:SourceField's mode field and associated _common.mapping:SourceFieldMode enum

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[github-actions]

Changes Analysis

Commit SHA: 674748e
Comparing To SHA: 1eb43f6

API Changes

Summary

├─┬Info
│ └──[🔀] version (4:12)
└─┬Components
  ├──[➖] schemas (38830:7)❌ 
  └─┬_common.mapping:SourceField
    └──[➖] properties (38827:9)❌ 

Document Element	Total Changes	Breaking Changes
info	1	0
components	2	2

• ❌ BREAKING Changes: 2 out of 3
• Modifications: 1
• Removals: 2
• Breaking Removals: 2

Report

The full API changes report is available at: https://github.com/opensearch-project/opensearch-api-specification/actions/runs/11619710912/artifacts/2130591353

API Coverage

	Before	After	Δ
Covered (%)	588 (57.59 %)	588 (57.59 %)	0 (0 %)
Uncovered (%)	433 (42.41 %)	433 (42.41 %)	0 (0 %)
Unknown	35	35	0

[github-actions]

Spec Test Coverage Analysis

Total	Tested
510	321 (62.94 %)

[dblock]

Needs a rebase, thanks.

Since this is a breaking change, bump the version from 0.1.1 to 0.2.0.

The merge-base changed after approval.