Trends report

[erfanio]

Trends report is available to collaborators at https://llm-exp.oss-fuzz.com/trend-reports/index.html

This PR

• Adds trends report web page
• Adds a cloud run function to update trend-reports/index.json in GCS
• Adds a cloud run function to update web page files (html, js, css)
• Adds a script to deploy cloud run functions (this script needs to be run manually after every change to the code)
• Moves trends report summary generation tool to a subdirectory so everything related to trends report is together

@DavidKorczynski @DonggeLiu please let me know if you want anything else added to the trends report

[erfanio]

/gcbrun exp -n erfanio

[DonggeLiu]

Wow this is truly amazing, thanks @erfanio!
It makes comparing metrics across experiments so much easier, e.g., we can easily see the build rate improvements in 2024 Nov.

I just returned to work and might need a bit more time to read the code, but by looking at the trend report I think it's already great!

[DonggeLiu]

Some minor suggestions as discussed:

1. Include the results of incomplete experiments (e.g., 2024-11-08-weekly-all).

2. Use build rate (% values) instead of absolute values in the Overview plot, e.g., 30.30%.

3. Use % for build rate, percentage coverage gain, etc. For example 0.1% coverage gain (instead of 0.001). Some small numbers might be rounded to 0 because of this:
   

4. Maybe remove reportName in plots? It can be misleading given it has to be distant from the long x-axis labels, which are self-explanatory.

5. Plot line color indicator for function signatures, e.g., mention that in the table beneath the plot? Omit this if it's too complex.

6. Add copyright headers with the correct year.