feat: add support for custom tag order

[alespour]

Proposed Changes

Adds support for specifying column (tag) order during ingestion via new tagOrder write option. This is primarily intended for the initial write, where sorting tags by query priority can significantly impact query performance:
https://docs.influxdata.com/influxdb3/enterprise/write-data/best-practices/schema-design/#sort-tags-by-query-priority

Also includes minor write performance optimizations.

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• A test has been added if appropriate
• Tests pass
• Commit messages are conventional

[codecov]

Codecov Report

❌ Patch coverage is 94.93671% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.90%. Comparing base (2366504) to head (24df6b4).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/main/java/com/influxdb/v3/client/Point.java	94.59%	0 Missing and 2 partials ⚠️
...nfluxdb/v3/client/internal/InfluxDBClientImpl.java	88.23%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #363      +/-   ##
==========================================
+ Coverage   87.26%   87.90%   +0.63%     
==========================================
  Files          20       20              
  Lines        1343     1397      +54     
  Branches      229      241      +12     
==========================================
+ Hits         1172     1228      +56     
  Misses         81       81              
+ Partials       90       88       -2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Copilot]

Pull request overview

Adds a tagOrder write option to control tag (column) ordering during ingestion, enabling users to optimize InfluxDB query performance by ordering tags by query priority.

Changes:

• Introduces tagOrder in WriteOptions (builder, storage, equality/hash, safe accessor).
• Updates point serialization to accept default tags + preferred tag ordering.
• Expands tests and documentation to cover ordered-tag writes and serialization behavior.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/main/java/com/influxdb/v3/client/write/WriteOptions.java	Adds tagOrder option plumbing (field, ctor/builder, equals/hashCode, accessor).
src/main/java/com/influxdb/v3/client/internal/InfluxDBClientImpl.java	Uses the new ordered serialization path when writing Point instances.
src/main/java/com/influxdb/v3/client/Point.java	Adds toLineProtocol overload and tag-merge/reorder logic for serialization.
src/test/java/com/influxdb/v3/client/write/WriteOptionsTest.java	Adds tests for tagOrder, and extends equals/hashCode coverage.
src/test/java/com/influxdb/v3/client/PointTest.java	Adds coverage for line protocol serialization with default tags + tag order.
src/test/java/com/influxdb/v3/client/InfluxDBClientWriteTest.java	Adds an integration-style test verifying ordered tags are sent on write.
README.md	Documents how to use tagOrder via WriteOptions.
CHANGELOG.md	Notes the new tagOrder feature and links to InfluxDB guidance.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 1 comment.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated no new comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[bednar]

LGTM 🚀