[Improve](segment) Put Segment footer into index page cache

[eldenmoon]

This commit modified the caching logic for the Segment footer.

Previously, the Segment footer was cached in the DATA_PAGE cache. This was incorrect as the footer is metadata, not data. This commit changes it to use the more appropriate INDEX_PAGE cache.

Additionally, the calculation for _meta_mem_usage has been adjusted for better accuracy. The footer size is no longer included in the calculation since it's now managed by the StoragePageCache. The memory estimation for column readers is also updated to use
config::max_segment_partial_column_cache_size for a more realistic value.

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[Thearas]

Thank you for your contribution to Apache Doris.
Don't know what should be done next? See How to process your PR.

Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
2. Which behaviors were modified. What was the previous behavior, what is it now, why was it modified, and what possible impacts might there be.
3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[eldenmoon]

run buildall

[eldenmoon]

run buildall

[eldenmoon]

run buildall

[csun5285]

LGTM

[github-actions]

PR approved by anyone and no changes requested.

[hello-stephen]

BE UT Coverage Report

Increment line coverage 100.00% (5/5) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	52.40% (17648/33677)
Line Coverage	37.66% (160372/425883)
Region Coverage	32.17% (122094/379533)
Branch Coverage	33.53% (53551/159732)

[doris-robot]

ClickBench: Total hot run time: 30.68 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit 9c57d4b9627b0b55019ddc7242a8f132d9de4356, data reload: false

query1	0.05	0.05	0.05
query2	0.09	0.05	0.06
query3	0.27	0.09	0.09
query4	1.61	0.12	0.12
query5	0.30	0.26	0.25
query6	1.20	0.67	0.64
query7	0.03	0.02	0.03
query8	0.06	0.05	0.05
query9	0.61	0.52	0.51
query10	0.61	0.57	0.57
query11	0.16	0.11	0.11
query12	0.15	0.11	0.12
query13	0.63	0.63	0.61
query14	1.03	1.04	1.05
query15	0.89	0.86	0.86
query16	0.42	0.40	0.39
query17	1.04	1.07	1.06
query18	0.22	0.20	0.20
query19	2.23	1.98	2.01
query20	0.02	0.01	0.01
query21	15.70	0.95	0.58
query22	0.77	1.06	0.70
query23	15.05	1.36	0.64
query24	6.89	2.05	0.88
query25	0.50	0.25	0.15
query26	0.57	0.16	0.14
query27	0.06	0.06	0.06
query28	10.20	1.36	0.94
query29	12.54	3.91	3.25
query30	0.27	0.13	0.12
query31	2.83	0.61	0.38
query32	3.26	0.56	0.47
query33	3.20	3.03	3.18
query34	16.17	5.50	4.86
query35	4.93	4.89	4.91
query36	0.70	0.53	0.49
query37	0.10	0.08	0.08
query38	0.06	0.04	0.04
query39	0.03	0.02	0.03
query40	0.17	0.15	0.14
query41	0.09	0.04	0.03
query42	0.04	0.03	0.03
query43	0.04	0.04	0.04
Total cold run time: 105.79 s
Total hot run time: 30.68 s

[hello-stephen]

BE Regression && UT Coverage Report

Increment line coverage 100.00% (5/5) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	71.17% (23409/32890)
Line Coverage	57.57% (244538/424730)
Region Coverage	52.97% (203681/384538)
Branch Coverage	54.59% (87544/160363)

[HappenLee]

LGTM

[github-actions]

PR approved by at least one committer and no changes requested.